- Email: [email protected]
A method for estimating world maritime employment
Transportation Research Part E 35 (1999) 183±189
www.elsevier.com/locate/tre
A method for estimating world maritime employment K.X. Li *, J. Wonham University of Wales Cardi, Department of Maritime Studies and International Transport, Cardi CF1 3YP, UK Received 6 March 1998; received in revised form 22 December 1998; accepted 20 January 1999
Abstract Compared with technical research on ships, there is lack of systematic data and research on maritime labour, their number, education and manning eciency. Due to the high mobility of the profession and complication of jurisdictions, there is no exact ®gure of the number of seamen worldwide. This paper establishes a method to estimate maritime labour worldwide as well as on open-registry ¯eets. Ó 1999 Elsevier Science Ltd. All rights reserved.
1. Introduction Worldwide data on merchant vessels, e.g., numbers of ships, sizes, types, numbers of new building and accidental total loss, have been available for many years. 1 Complete data on the employment of seamen is still not available on a worldwide scale, and not even at national levels in some maritime nations. 2 Calculations of maritime labour demand and supply are based on questionnaires (BIMCO/ISF, 1990, 1995). The fatalities and injuries to seamen worldwide have to be approximated based on data of individual ¯eets (Goss et al., 1991; Li, 1998). Without ``safer, healthier and happier seamen'', the aim of ``safer ships and cleaner oceans'' can only be achieved to a limited extent. There is justi®cation in stating that ``of all sections of the community, seafaring men . . . have been the most ignored and therefore the worst treated''(Kitchen, 1980). Furthermore, it can be argued that the most ignored group of seamen is those working on openregistry ships. The fact that ``The open-registry ¯eets were operating without eective government
*
Corresponding author. Fax: 0171-772-8200; e-mail: [email protected] Which may date back to 1934, the establishment of the Society of Lloyd's Register, which now has more than 3800 sta based at over 255 oces worldwide. Its statistics on worldwide ¯eets is considered as both authentic and comprehensive. See Farthing (1993). 2 In 1997, the number of seamen in UK, a traditional maritime nation, was based on estimation. See McConville et al. (1998). 1
1366-5545/99/$ ± see front matter Ó 1999 Elsevier Science Ltd. All rights reserved. PII: S 1 3 6 6 - 5 5 4 5 ( 9 9 ) 0 0 0 0 7 - 1
184
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
control or regulation'' UNCTAD (1979) results in not only the poor safety records of openregistry ¯eets (Doganis and Metaxa, 1976), but also non-availability of necessary data, especially data on seamen, for loss prevention and further research. Chapman commented that ``This lack of academic attention is a shame in that the growth of international economic interdependence has increased the importance of the maritime industry worldwide'' (Chapman, 1992). Basic information about seamen is also vital for maritime policy-making and legislation at both national and international levels, national maritime policy-making, and academic research. For example, the calculation of demand and supply of maritime labour, and the planning of maritime education and training requires estimation of current and prospective maritime employment. This study tries to establish a model to estimate the number of seamen worldwide and on open-registry ¯eets. The method, if supplemented by data from additional countries, could be tested and developed into a useful tool for estimation of maritime employment, trends in labour eciency, and to help estimate future supply and demand. 2. Scope of open registers Open-registry ¯eets in the study include 17 ¯eets, i.e., Bahamas, Bermuda, Cyprus, Liberia, Malta, Panama, Vanuatu, Antigua and Barbuda, Barbados, Belize, Gibraltar, Honduras, Marshall Islands, Mauritius, Saint Vincent, Sri Lanka, and Tuvalu, which are covered by UNCTAD and ITF. 3 ITF considers any ``countries which oer their maritime ¯ag registration to owners from another country'' as open registers, and accordingly a list of all open-registers is given (ITF, 1998). The list covers the seven major open-registry countries given by UNCTAD, and also includes other small registers or second registers. Among those, some are being considered as open registers only on a ship by ship basis, e.g., Philippines, Singapore, Luxembourg, and Isle of Man. Some secondary registers are mainly for their own shipowners, e.g., in 1996, 96.5% of the total tonnage in Danish International Register (DIS), and 88.6% in Norwegian International Register (NIS) belonged to their own nationals (UNCTAD, 1997). For the purposes of this study they are not considered as open registers. Concerning the type and size of ship, the study includes all types of propelled sea-going merchant ships, including cargo and passenger ships that are no less than 100 gross tonnage (gt), in order to be compatible with Lloyd's data. 3. Data The UK is a traditional maritime nation. Its ¯eet, notwithstanding its decline over several decades, is still a principal ¯eet consisting of dierent types and sizes of ships. From the viewpoint
3 The ®rst seven countries, i.e., Bahamas, Bermuda, Cyprus, Liberia, Malta, Panama, and Vanuatu are listed as major open-registry countries by UNCTAD, see UNCTAD (1997). The other 10 counties, i.e., Antigua and Barbuda, Barbados, Belize, Gibraltar, Honduras, Marshall Islands, Mauritius, Saint Vincent, Sri Lanka, and Tuvalu are listed as foc (¯ag of convenience) ¯eets by ITF (The International Transport Worker's Federation).
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
185
of the size of ¯eet, diversity of ship types, and structure of seamen, the UK ¯eet is believed adequate for the modelling study, i.e., UK data are used to establish a link between ship size and manning requirements, and how this is changing over time. Data on seamen are collected from dierent sources, which, however, all are considered as ocial sources. 4 Data on the UK seamen are not available after 1990. 5 We suspect there was a marginal decline in its average manning level due to multipurpose crewing, however, nothing signi®cant. Thus, it is supposed that after 1990 the manning ``level'' remains the same as in 1990. From the data collected, it is clear that the average manning level in the UK ¯eet has been constantly falling from 20.27/ship in 1975 to 10.25/ship in 1990. It is also observed that there is no tendency of falling in employment ``ratio'' (employed/ posts), which kept stable at around 1:1.21. Thus, for the purpose of calculation, the average ratio of 1.21 is used as the employed ratio after 1990. Before 1990, UK employment ratio each year is used respectively for the calculation in the cases of world and open registry ¯eets. Data on ships in Tables 1 and 2 relating to the world, UK and open registry ¯eets are combined from the Statistical Tables, published by Lloyd's Register of Shipping. 4. Number of seamen The ``number of seamen'' is not as simple of a concept as it might appear. In dierent publications, it may have a quite dierent meaning. Sometimes it means the number of seamen at risk (or the number of seamen's posts), which is the number of seamen who are actually at work on board ships at any given time. It sometimes means the number of seamen employed by shipping companies, i.e., the number of seamen who actually maintain an employment contract with shipping companies, which includes seamen on shore because of holiday or illness. It sometimes may refer to the number of registered seamen, or the number of licensed seamen within a country. In this study ``Seamen's posts'' refers to the number of seamen at risk, i.e., on ships, and ``number of seamen'' is the number under contract to a shipping company if not otherwise indicated. Hence these are the de®nitions for the extrapolation to the world and FOC ¯eets. As mentioned previously, the size of ¯eet, diversity of ship types, and structure of seamen in the UK ¯eet are believed adequate for the model study, applying to the world and open registry ¯eets. Because of the competition on cost saving and the availability of new technology, it is observed in UK ¯eet in Table 1, that manning levels have been falling steadily over the years. Each year old ships requiring high manning levels are replaced with new ships with high technology, and requires fewer crew. Theoretically, each year has a dierent average manning level, which can be expected to decline over time due to the development of technology. Time can be considered as an parameter of average manning level of a ¯eet. Another factor aecting the manning level of a ¯eet is the average size of ship in the ¯eet. In the UK ¯eet, the average size has fallen from 9154 gt in 1977 to 2713 gt in 1996. The ships that ¯agged 4
See notes (b) and (c) under Table 1. Data on seamen registered with the Merchant Navy Establishment (MNE) was available till 31 July 1990 when the MNE ended. After that, data is available from Chamber of Shipping. However, the data only includes seamen with Chamber's members, whose ships ¯y not only UK ¯ag. Thus, the data is not relevant for present study. The Stationery Oce (1997) : Merchant ¯eet statistics, p. 86. 5
186
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
Table 1 Data of UK's ships and seamen (1975±92) Year
Ships Number
1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 Average
3622 3549 3432 3359 3211 3181 2975 2826 2570 2468 2378 2256 1925 1909 1850 1784
Seamen a
gt (000) 33,157 32,923 31,646 30,897 27,951 27,135 25,419 22,505 19,122 15,874 14,344 11,561 8505 8260 7646 6716
a
b
Average size (gt)
Posts
9154 9277 9221 9198 8705 8530 8544 7964 7440 6432 6032 5125 4418 4327 4133 3765
73,400 70,900 69,600 66,000 60,400 57,900 53,700 47,500 40,000 34,500 34,500 24,800 24,703 22,629 20,958 18,289
Employed 90,531 90,406 88,335 82,626 74,183 71,343 64,229 54,955 45,826 39,776 37,534 30,019 28,772 28,601 26,383 24,100
c
Ratio
d
Level
1.23 1.28 1.27 1.25 1.23 1.23 1.20 1.16 1.15 1.15 1.09 1.21 1.16 1.26 1.26 1.32
20.27 19.98 20.28 19.65 18.81 18.20 18.05 16.81 15.56 13.98 14.51 10.99 12.83 11.85 11.33 10.25
1.21
15.83
d
a
1975±90: Statistical Tables, Lloyd's Register of Shipping, London. 1975±86: Transport Committee of House of Commons (1988): Decline in the UK registered merchant ¯eet, vol. I, Table 8, p. pxv, London: HMSO; 1987±90: Transport statistics report ± merchant ¯eet statistics (1994, 1996), London: The Stationery Oce. c 1976±92: General Council of British Shipping, quoted in The Department of Transport (1990): British shipping ± challenges and opportunities, London: HMSO, Table 2.9, p. 33. 1975 is 1974's ®gure, Board of Trade, quoted in Kitchen (1980): The Employment of Merchant Seamen. Croom Helm London. d (Employment) Ratio No. of Employed/Posts;(Manning) Level Posts/ships. b
out from UK ¯eet tended to be larger ships, such as tankers and bulkers. This may also explain that the general average size of ship (12,990 gt) in open registry ¯eets is much larger than in the UK (5912 gt) and the world ¯eet (5615 gt). It is clear that the size of ship in a ¯eet will aect its manning level, i.e., the larger the size of ships the higher manning level. To test these hypotheses, manning levels are positively and almost perfectly correlated with the variable of the size of the ¯eet (R 0.98), and manning levels are negatively and almost perfectly correlated with the variable for year (R ÿ0.97). Combining the above reasoning and test, a formula can be developed to describe the average manning level of a ¯eet with variables of ``year'' and the average ``size'' of the ¯eet: Level C B1 Year B2 Size; 1 where C is the constant, B1 the regression coecient for independent variable of year, and B2 is the regression coecient for independent variable of the average size of ships in the ¯eet. A linear Regression produces a constant C 675.81, and coecient B1 ÿ0:336; B2 0:00095 (see the regression results in Table 3). The R square 0.96756 means that 98% of the variance in UK's data is explained by these variables. The signi®cance level is <0.001, which implies that a maximum of one in a thousand samples might constitute a deviant sample or that the null hypothesis
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
187
Table 2 Seamen's number on foc ¯eets (1977±96) World ships
a
World seamen
b
foc ships
a
foc seamen
b
Year
Number Size
Level
Posts
Number
Number
Size
Level
Posts
Number
1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996
69,020 71,129 73,832 73,865 75,151 76,106 76,068 76,395 75,266 75,281 75,799 75,025 78,301 78,913 79,726 80,655 80,676 82,890 84,264 76,315
5794 5882 5807 5687 5697 5652 5553 5504 5449 5380 5278 5270 5397 5441 5402 5584 5677 5898 5919 6027
16.52 16.27 15.86 15.41 15.08 14.70 14.27 13.89 13.50 13.10 12.67 12.32 12.11 11.81 11.44 11.28 11.03 10.90 10.59 10.35
1,140,292 1,157,191 1,171,021 1,138,326 1,133,586 1,119,105 1,085,791 1,061,238 1,016,296 986,231 960,187 924,592 948,079 932,255 912,114 909,554 889,854 903,820 892,153 790,150
1,448,171 1,446,489 1,440,355 1,400,141 1,360,304 1,298,162 1,248,660 1,220,424 1,107,763 1,193,340 1,113,817 1,164,986 1,194,580 1,230,576 1,203,990 1,200,612 1,174,607 1,193,043 1,177,642 1,042,998
7584 7730 7912 8118 8614 9350 9371 9543 9558 10,513 10,932 11,012 11,563 12,608 13,644 14,486 15,217 15,694 16,516 10,862
14,392 13,990 14,089 13,796 13,064 12,497 11,742 12,096 12,191 12,334 12,447 12,449 12,647 12,672 12,972 12,979 12,045 13,229 13,878 14,297
24.70 23.98 23.74 23.12 22.09 21.22 20.16 20.16 19.92 19.72 19.49 19.15 19.00 18.69 18.64 18.31 17.09 17.88 18.16 18.22
187,318 185,368 187818 187,713 190,288 198,364 188,924 192,395 190,352 207,268 213,029 210,905 219,748 235,665 254,331 265,250 260,004 280,551 299,884 197,901
237,893 231,709 231,016 230,887 228,345 230,102 217,262 221,255 207,484 250,794 247,114 265,740 276,882 311,078 335,716 350,130 343,205 370,327 395,847 261,229
Average 76,734
5615
13
12,990
20
217,654
272,201
a b
1,003,592
1,243,033
11,041
Lloyd's Register of Shipping: Statistical Tables (1977±91), World Fleet Statistic (1992±96). Calculations of this study.
will be erroneously rejected. In brief, the test of formula with the collected date is quite acceptable from a statistical viewpoint. Accordingly, it is expected the manning level can be calculated reliably with given ``time'' and size by formula (2): Level 675:81 ÿ 0:336 Year 0:00095 Size 2:253 ÿ2:24 2:789
:
2
stands for significant level < 0:0001
To test the reliability of the method, an estimate of world seamen can be produced with the world ship data in Table 2. For example in 1990, the world had 78,913 ships, average size is 5441 gt, the world manning level should be Level 675:81 ÿ 0:336 1990 0:00095 5441 11:81 2:253 ÿ2:24 2:789
3
stands for significant level < 0:0001; thus the world seamen's posts can be calculated as Posts No: of Ships Mainning level 78; 913 11:81 932; 255:
4
188
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
Table 3 Output of multiple regression test on UK ¯eet Dependent variable: Average manning level in the ¯eet Variable(s) entered on step number 1. Time ± year 2. Average size of ships Multiple R, 0.98365 R square, 0.96756 Adjusted R square, 0.96257 Standard error, 0.70042 Analysis of variance
DF
Regression 2 Residual 13 F 193.87746, Signif F 0.0000 Variables in the equation Variable B Size Year Constant
9.51977 ´ 10 ÿ0.335906 675.088553
Sum of squares
Mean square
190.22930 6.37769
95.11465 0.49059
SE B ÿ4
ÿ4
3.4134 ´ 10 0.149948 299.589004
Beta
T
Sig T
0.549939 ÿ0.441731
2.789 ÿ2.240 2.253
0.0154 0.0432 0.0421
The number of seamen employed worldwide in 1990 should be the posts multiplying the average of employment ratio in 1990, i.e., 1.32, thus No: of seamen Posts Ratio 932; 255 1:32 1; 230; 576: 5 Similarly, the number of open-registry seamen can be determined. For example, in 1990, foc had 12,608 ships, the average size was 12,672 gt, the average manning level should be as Level 675:81 ÿ 0:336 1990 0:00095 12; 672 18:69 2:253 ÿ2:24 2:789
6
stands for significant level < 0:0001: Thus, we can have foc posts of 235,665, and the number of employed foc seamen of 311,078 in 1990. Similarly in 1996, there were 197,901 on board open-registry ships at any given time, and 261,229 employed by open-registry ¯eets. Consequently, we can produce the number of seaman in each year (Table 2). According to BIMCO/ISF (1990) the number of worldwide seamen in 1990 was 1.24 million, which is very close to 1.23 million in this study. This may con®rm the reliability of the method used in this study. At the very least, the model can be used as a test method to contrast with the questionnaire method adopted in the BIMCO/ISF manpower study. 5. Conclusion As observed from UK data, the Maritime Employment Ration (Employed/Posts) has not changed much during the last 20 years, average at 1.21:1, whilst the Manning Level (Posts/Ship)
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
189
has been declining from 20.27/ship to 10.25/ship. According to the study, there were a total of 790,150 seamen's posts and 1,042,998 seamen in service worldwide in 1996. During the period of 1977±1996, the average annual posts were 1,003,592, annual average seamen in service were 1,243,033 worldwide. In 1996, there were 197,901 posts and 261,229 seamen employed on openregistry ¯eets. In the period of 1977±1996, the annual average posts on open-registry ships were 217,654, and the annual average seamen employed on open-registry ¯eets were 272,201. There is one out of four of total world seamen working on board of open-registry ships. There is a great need for the co-ordination and uni®cation in seamen's data collection worldwide. Acknowledgements Thanks go to the Editor, Prof. W.G. Waters II and three reviewers for their suggestions that led to substantial improvements of the paper. The views expressed herein however are solely those of the authors, who are responsible for any errors and omissions. References BIMCO/ISF, 1990, 1995. The worldwide demand for and supply of seafarers, prepared by the Institute for Employment Research at University of Warwick. A detailed examination on the survey, please see; Li, K.X., Wonham, J., 1999. Who mans the world ¯eet ± a follow-up to the BIMCO/ISF manpower survey. Maritime Policy and Management, 1999, forth coming. Chapman, P.K., 1992. Trouble on board: the plight of international seafarers, p. xix. Doganis, R.S., Metaxa, B.N., 1976. The impact of ¯ags of convenience. Polytechnic of Central London, September 1976, 79, 103; Metaxa, B.N., 1985. Flags of convenience ± a study of internationalisation. Gower, England, Hants, pp. 92, 99. Farthing, B., 1993. Lloyd's List Practical Guides on International Shipping. Lloyd's of London Press, 26, 39. Goss, R.O., Nicholls, C., Pettit, S.J., 1991. Seamen's accidental deaths and injuries worldwide: A methodology and some estimates. Journal of Navigation 44 (2) 271±275. Li, K.X., 1998. Seamen's accidental deaths worldwide: A new approach. Maritime Policy and Management. ITF, 1998. ITF Internet home page (http://www.itf.org.uk/sections/mar/foceng.html). Kitchen, J.S., 1980. The Employment of Merchant Seamen. Croom Helm, London, p. 1. McConville, J., Glen, D.R., Dowden, J., 1998. UK seafarers anaysis 1997. Centre For International Transport Management, London Guildhall University. Issues in International Transport Management 1 (3). The Stationery Oce, 1997. Merchant Fleet Statistics, p. 86. UNCTAD, 1979. Bene®cial ownership of open-registry ¯eets: report by the UNCTAD secretariat. TD/222/Supp 10. UNCTAD, 1997. Review of maritime transport. UNCTAD/RTM/97/1. UN. New York, p. 31.
www.elsevier.com/locate/tre
A method for estimating world maritime employment K.X. Li *, J. Wonham University of Wales Cardi, Department of Maritime Studies and International Transport, Cardi CF1 3YP, UK Received 6 March 1998; received in revised form 22 December 1998; accepted 20 January 1999
Abstract Compared with technical research on ships, there is lack of systematic data and research on maritime labour, their number, education and manning eciency. Due to the high mobility of the profession and complication of jurisdictions, there is no exact ®gure of the number of seamen worldwide. This paper establishes a method to estimate maritime labour worldwide as well as on open-registry ¯eets. Ó 1999 Elsevier Science Ltd. All rights reserved.
1. Introduction Worldwide data on merchant vessels, e.g., numbers of ships, sizes, types, numbers of new building and accidental total loss, have been available for many years. 1 Complete data on the employment of seamen is still not available on a worldwide scale, and not even at national levels in some maritime nations. 2 Calculations of maritime labour demand and supply are based on questionnaires (BIMCO/ISF, 1990, 1995). The fatalities and injuries to seamen worldwide have to be approximated based on data of individual ¯eets (Goss et al., 1991; Li, 1998). Without ``safer, healthier and happier seamen'', the aim of ``safer ships and cleaner oceans'' can only be achieved to a limited extent. There is justi®cation in stating that ``of all sections of the community, seafaring men . . . have been the most ignored and therefore the worst treated''(Kitchen, 1980). Furthermore, it can be argued that the most ignored group of seamen is those working on openregistry ships. The fact that ``The open-registry ¯eets were operating without eective government
*
Corresponding author. Fax: 0171-772-8200; e-mail: [email protected] Which may date back to 1934, the establishment of the Society of Lloyd's Register, which now has more than 3800 sta based at over 255 oces worldwide. Its statistics on worldwide ¯eets is considered as both authentic and comprehensive. See Farthing (1993). 2 In 1997, the number of seamen in UK, a traditional maritime nation, was based on estimation. See McConville et al. (1998). 1
1366-5545/99/$ ± see front matter Ó 1999 Elsevier Science Ltd. All rights reserved. PII: S 1 3 6 6 - 5 5 4 5 ( 9 9 ) 0 0 0 0 7 - 1
184
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
control or regulation'' UNCTAD (1979) results in not only the poor safety records of openregistry ¯eets (Doganis and Metaxa, 1976), but also non-availability of necessary data, especially data on seamen, for loss prevention and further research. Chapman commented that ``This lack of academic attention is a shame in that the growth of international economic interdependence has increased the importance of the maritime industry worldwide'' (Chapman, 1992). Basic information about seamen is also vital for maritime policy-making and legislation at both national and international levels, national maritime policy-making, and academic research. For example, the calculation of demand and supply of maritime labour, and the planning of maritime education and training requires estimation of current and prospective maritime employment. This study tries to establish a model to estimate the number of seamen worldwide and on open-registry ¯eets. The method, if supplemented by data from additional countries, could be tested and developed into a useful tool for estimation of maritime employment, trends in labour eciency, and to help estimate future supply and demand. 2. Scope of open registers Open-registry ¯eets in the study include 17 ¯eets, i.e., Bahamas, Bermuda, Cyprus, Liberia, Malta, Panama, Vanuatu, Antigua and Barbuda, Barbados, Belize, Gibraltar, Honduras, Marshall Islands, Mauritius, Saint Vincent, Sri Lanka, and Tuvalu, which are covered by UNCTAD and ITF. 3 ITF considers any ``countries which oer their maritime ¯ag registration to owners from another country'' as open registers, and accordingly a list of all open-registers is given (ITF, 1998). The list covers the seven major open-registry countries given by UNCTAD, and also includes other small registers or second registers. Among those, some are being considered as open registers only on a ship by ship basis, e.g., Philippines, Singapore, Luxembourg, and Isle of Man. Some secondary registers are mainly for their own shipowners, e.g., in 1996, 96.5% of the total tonnage in Danish International Register (DIS), and 88.6% in Norwegian International Register (NIS) belonged to their own nationals (UNCTAD, 1997). For the purposes of this study they are not considered as open registers. Concerning the type and size of ship, the study includes all types of propelled sea-going merchant ships, including cargo and passenger ships that are no less than 100 gross tonnage (gt), in order to be compatible with Lloyd's data. 3. Data The UK is a traditional maritime nation. Its ¯eet, notwithstanding its decline over several decades, is still a principal ¯eet consisting of dierent types and sizes of ships. From the viewpoint
3 The ®rst seven countries, i.e., Bahamas, Bermuda, Cyprus, Liberia, Malta, Panama, and Vanuatu are listed as major open-registry countries by UNCTAD, see UNCTAD (1997). The other 10 counties, i.e., Antigua and Barbuda, Barbados, Belize, Gibraltar, Honduras, Marshall Islands, Mauritius, Saint Vincent, Sri Lanka, and Tuvalu are listed as foc (¯ag of convenience) ¯eets by ITF (The International Transport Worker's Federation).
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
185
of the size of ¯eet, diversity of ship types, and structure of seamen, the UK ¯eet is believed adequate for the modelling study, i.e., UK data are used to establish a link between ship size and manning requirements, and how this is changing over time. Data on seamen are collected from dierent sources, which, however, all are considered as ocial sources. 4 Data on the UK seamen are not available after 1990. 5 We suspect there was a marginal decline in its average manning level due to multipurpose crewing, however, nothing signi®cant. Thus, it is supposed that after 1990 the manning ``level'' remains the same as in 1990. From the data collected, it is clear that the average manning level in the UK ¯eet has been constantly falling from 20.27/ship in 1975 to 10.25/ship in 1990. It is also observed that there is no tendency of falling in employment ``ratio'' (employed/ posts), which kept stable at around 1:1.21. Thus, for the purpose of calculation, the average ratio of 1.21 is used as the employed ratio after 1990. Before 1990, UK employment ratio each year is used respectively for the calculation in the cases of world and open registry ¯eets. Data on ships in Tables 1 and 2 relating to the world, UK and open registry ¯eets are combined from the Statistical Tables, published by Lloyd's Register of Shipping. 4. Number of seamen The ``number of seamen'' is not as simple of a concept as it might appear. In dierent publications, it may have a quite dierent meaning. Sometimes it means the number of seamen at risk (or the number of seamen's posts), which is the number of seamen who are actually at work on board ships at any given time. It sometimes means the number of seamen employed by shipping companies, i.e., the number of seamen who actually maintain an employment contract with shipping companies, which includes seamen on shore because of holiday or illness. It sometimes may refer to the number of registered seamen, or the number of licensed seamen within a country. In this study ``Seamen's posts'' refers to the number of seamen at risk, i.e., on ships, and ``number of seamen'' is the number under contract to a shipping company if not otherwise indicated. Hence these are the de®nitions for the extrapolation to the world and FOC ¯eets. As mentioned previously, the size of ¯eet, diversity of ship types, and structure of seamen in the UK ¯eet are believed adequate for the model study, applying to the world and open registry ¯eets. Because of the competition on cost saving and the availability of new technology, it is observed in UK ¯eet in Table 1, that manning levels have been falling steadily over the years. Each year old ships requiring high manning levels are replaced with new ships with high technology, and requires fewer crew. Theoretically, each year has a dierent average manning level, which can be expected to decline over time due to the development of technology. Time can be considered as an parameter of average manning level of a ¯eet. Another factor aecting the manning level of a ¯eet is the average size of ship in the ¯eet. In the UK ¯eet, the average size has fallen from 9154 gt in 1977 to 2713 gt in 1996. The ships that ¯agged 4
See notes (b) and (c) under Table 1. Data on seamen registered with the Merchant Navy Establishment (MNE) was available till 31 July 1990 when the MNE ended. After that, data is available from Chamber of Shipping. However, the data only includes seamen with Chamber's members, whose ships ¯y not only UK ¯ag. Thus, the data is not relevant for present study. The Stationery Oce (1997) : Merchant ¯eet statistics, p. 86. 5
186
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
Table 1 Data of UK's ships and seamen (1975±92) Year
Ships Number
1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 Average
3622 3549 3432 3359 3211 3181 2975 2826 2570 2468 2378 2256 1925 1909 1850 1784
Seamen a
gt (000) 33,157 32,923 31,646 30,897 27,951 27,135 25,419 22,505 19,122 15,874 14,344 11,561 8505 8260 7646 6716
a
b
Average size (gt)
Posts
9154 9277 9221 9198 8705 8530 8544 7964 7440 6432 6032 5125 4418 4327 4133 3765
73,400 70,900 69,600 66,000 60,400 57,900 53,700 47,500 40,000 34,500 34,500 24,800 24,703 22,629 20,958 18,289
Employed 90,531 90,406 88,335 82,626 74,183 71,343 64,229 54,955 45,826 39,776 37,534 30,019 28,772 28,601 26,383 24,100
c
Ratio
d
Level
1.23 1.28 1.27 1.25 1.23 1.23 1.20 1.16 1.15 1.15 1.09 1.21 1.16 1.26 1.26 1.32
20.27 19.98 20.28 19.65 18.81 18.20 18.05 16.81 15.56 13.98 14.51 10.99 12.83 11.85 11.33 10.25
1.21
15.83
d
a
1975±90: Statistical Tables, Lloyd's Register of Shipping, London. 1975±86: Transport Committee of House of Commons (1988): Decline in the UK registered merchant ¯eet, vol. I, Table 8, p. pxv, London: HMSO; 1987±90: Transport statistics report ± merchant ¯eet statistics (1994, 1996), London: The Stationery Oce. c 1976±92: General Council of British Shipping, quoted in The Department of Transport (1990): British shipping ± challenges and opportunities, London: HMSO, Table 2.9, p. 33. 1975 is 1974's ®gure, Board of Trade, quoted in Kitchen (1980): The Employment of Merchant Seamen. Croom Helm London. d (Employment) Ratio No. of Employed/Posts;(Manning) Level Posts/ships. b
out from UK ¯eet tended to be larger ships, such as tankers and bulkers. This may also explain that the general average size of ship (12,990 gt) in open registry ¯eets is much larger than in the UK (5912 gt) and the world ¯eet (5615 gt). It is clear that the size of ship in a ¯eet will aect its manning level, i.e., the larger the size of ships the higher manning level. To test these hypotheses, manning levels are positively and almost perfectly correlated with the variable of the size of the ¯eet (R 0.98), and manning levels are negatively and almost perfectly correlated with the variable for year (R ÿ0.97). Combining the above reasoning and test, a formula can be developed to describe the average manning level of a ¯eet with variables of ``year'' and the average ``size'' of the ¯eet: Level C B1 Year B2 Size; 1 where C is the constant, B1 the regression coecient for independent variable of year, and B2 is the regression coecient for independent variable of the average size of ships in the ¯eet. A linear Regression produces a constant C 675.81, and coecient B1 ÿ0:336; B2 0:00095 (see the regression results in Table 3). The R square 0.96756 means that 98% of the variance in UK's data is explained by these variables. The signi®cance level is <0.001, which implies that a maximum of one in a thousand samples might constitute a deviant sample or that the null hypothesis
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
187
Table 2 Seamen's number on foc ¯eets (1977±96) World ships
a
World seamen
b
foc ships
a
foc seamen
b
Year
Number Size
Level
Posts
Number
Number
Size
Level
Posts
Number
1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996
69,020 71,129 73,832 73,865 75,151 76,106 76,068 76,395 75,266 75,281 75,799 75,025 78,301 78,913 79,726 80,655 80,676 82,890 84,264 76,315
5794 5882 5807 5687 5697 5652 5553 5504 5449 5380 5278 5270 5397 5441 5402 5584 5677 5898 5919 6027
16.52 16.27 15.86 15.41 15.08 14.70 14.27 13.89 13.50 13.10 12.67 12.32 12.11 11.81 11.44 11.28 11.03 10.90 10.59 10.35
1,140,292 1,157,191 1,171,021 1,138,326 1,133,586 1,119,105 1,085,791 1,061,238 1,016,296 986,231 960,187 924,592 948,079 932,255 912,114 909,554 889,854 903,820 892,153 790,150
1,448,171 1,446,489 1,440,355 1,400,141 1,360,304 1,298,162 1,248,660 1,220,424 1,107,763 1,193,340 1,113,817 1,164,986 1,194,580 1,230,576 1,203,990 1,200,612 1,174,607 1,193,043 1,177,642 1,042,998
7584 7730 7912 8118 8614 9350 9371 9543 9558 10,513 10,932 11,012 11,563 12,608 13,644 14,486 15,217 15,694 16,516 10,862
14,392 13,990 14,089 13,796 13,064 12,497 11,742 12,096 12,191 12,334 12,447 12,449 12,647 12,672 12,972 12,979 12,045 13,229 13,878 14,297
24.70 23.98 23.74 23.12 22.09 21.22 20.16 20.16 19.92 19.72 19.49 19.15 19.00 18.69 18.64 18.31 17.09 17.88 18.16 18.22
187,318 185,368 187818 187,713 190,288 198,364 188,924 192,395 190,352 207,268 213,029 210,905 219,748 235,665 254,331 265,250 260,004 280,551 299,884 197,901
237,893 231,709 231,016 230,887 228,345 230,102 217,262 221,255 207,484 250,794 247,114 265,740 276,882 311,078 335,716 350,130 343,205 370,327 395,847 261,229
Average 76,734
5615
13
12,990
20
217,654
272,201
a b
1,003,592
1,243,033
11,041
Lloyd's Register of Shipping: Statistical Tables (1977±91), World Fleet Statistic (1992±96). Calculations of this study.
will be erroneously rejected. In brief, the test of formula with the collected date is quite acceptable from a statistical viewpoint. Accordingly, it is expected the manning level can be calculated reliably with given ``time'' and size by formula (2): Level 675:81 ÿ 0:336 Year 0:00095 Size 2:253 ÿ2:24 2:789
:
2
stands for significant level < 0:0001
To test the reliability of the method, an estimate of world seamen can be produced with the world ship data in Table 2. For example in 1990, the world had 78,913 ships, average size is 5441 gt, the world manning level should be Level 675:81 ÿ 0:336 1990 0:00095 5441 11:81 2:253 ÿ2:24 2:789
3
stands for significant level < 0:0001; thus the world seamen's posts can be calculated as Posts No: of Ships Mainning level 78; 913 11:81 932; 255:
4
188
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
Table 3 Output of multiple regression test on UK ¯eet Dependent variable: Average manning level in the ¯eet Variable(s) entered on step number 1. Time ± year 2. Average size of ships Multiple R, 0.98365 R square, 0.96756 Adjusted R square, 0.96257 Standard error, 0.70042 Analysis of variance
DF
Regression 2 Residual 13 F 193.87746, Signif F 0.0000 Variables in the equation Variable B Size Year Constant
9.51977 ´ 10 ÿ0.335906 675.088553
Sum of squares
Mean square
190.22930 6.37769
95.11465 0.49059
SE B ÿ4
ÿ4
3.4134 ´ 10 0.149948 299.589004
Beta
T
Sig T
0.549939 ÿ0.441731
2.789 ÿ2.240 2.253
0.0154 0.0432 0.0421
The number of seamen employed worldwide in 1990 should be the posts multiplying the average of employment ratio in 1990, i.e., 1.32, thus No: of seamen Posts Ratio 932; 255 1:32 1; 230; 576: 5 Similarly, the number of open-registry seamen can be determined. For example, in 1990, foc had 12,608 ships, the average size was 12,672 gt, the average manning level should be as Level 675:81 ÿ 0:336 1990 0:00095 12; 672 18:69 2:253 ÿ2:24 2:789
6
stands for significant level < 0:0001: Thus, we can have foc posts of 235,665, and the number of employed foc seamen of 311,078 in 1990. Similarly in 1996, there were 197,901 on board open-registry ships at any given time, and 261,229 employed by open-registry ¯eets. Consequently, we can produce the number of seaman in each year (Table 2). According to BIMCO/ISF (1990) the number of worldwide seamen in 1990 was 1.24 million, which is very close to 1.23 million in this study. This may con®rm the reliability of the method used in this study. At the very least, the model can be used as a test method to contrast with the questionnaire method adopted in the BIMCO/ISF manpower study. 5. Conclusion As observed from UK data, the Maritime Employment Ration (Employed/Posts) has not changed much during the last 20 years, average at 1.21:1, whilst the Manning Level (Posts/Ship)
K.X. Li, J. Wonham / Transportation Research Part E 35 (1999) 183±189
189
has been declining from 20.27/ship to 10.25/ship. According to the study, there were a total of 790,150 seamen's posts and 1,042,998 seamen in service worldwide in 1996. During the period of 1977±1996, the average annual posts were 1,003,592, annual average seamen in service were 1,243,033 worldwide. In 1996, there were 197,901 posts and 261,229 seamen employed on openregistry ¯eets. In the period of 1977±1996, the annual average posts on open-registry ships were 217,654, and the annual average seamen employed on open-registry ¯eets were 272,201. There is one out of four of total world seamen working on board of open-registry ships. There is a great need for the co-ordination and uni®cation in seamen's data collection worldwide. Acknowledgements Thanks go to the Editor, Prof. W.G. Waters II and three reviewers for their suggestions that led to substantial improvements of the paper. The views expressed herein however are solely those of the authors, who are responsible for any errors and omissions. References BIMCO/ISF, 1990, 1995. The worldwide demand for and supply of seafarers, prepared by the Institute for Employment Research at University of Warwick. A detailed examination on the survey, please see; Li, K.X., Wonham, J., 1999. Who mans the world ¯eet ± a follow-up to the BIMCO/ISF manpower survey. Maritime Policy and Management, 1999, forth coming. Chapman, P.K., 1992. Trouble on board: the plight of international seafarers, p. xix. Doganis, R.S., Metaxa, B.N., 1976. The impact of ¯ags of convenience. Polytechnic of Central London, September 1976, 79, 103; Metaxa, B.N., 1985. Flags of convenience ± a study of internationalisation. Gower, England, Hants, pp. 92, 99. Farthing, B., 1993. Lloyd's List Practical Guides on International Shipping. Lloyd's of London Press, 26, 39. Goss, R.O., Nicholls, C., Pettit, S.J., 1991. Seamen's accidental deaths and injuries worldwide: A methodology and some estimates. Journal of Navigation 44 (2) 271±275. Li, K.X., 1998. Seamen's accidental deaths worldwide: A new approach. Maritime Policy and Management. ITF, 1998. ITF Internet home page (http://www.itf.org.uk/sections/mar/foceng.html). Kitchen, J.S., 1980. The Employment of Merchant Seamen. Croom Helm, London, p. 1. McConville, J., Glen, D.R., Dowden, J., 1998. UK seafarers anaysis 1997. Centre For International Transport Management, London Guildhall University. Issues in International Transport Management 1 (3). The Stationery Oce, 1997. Merchant Fleet Statistics, p. 86. UNCTAD, 1979. Bene®cial ownership of open-registry ¯eets: report by the UNCTAD secretariat. TD/222/Supp 10. UNCTAD, 1997. Review of maritime transport. UNCTAD/RTM/97/1. UN. New York, p. 31.