Short Sea Shipping: Alleviating the Environmental Impact of Economic Growth



Robert F. Mulligan, Ph.D.

Western Carolina University


Gary A. Lombardo, Ph.D.

United States Merchant Marine Academy




This paper quantifies the potential environmental benefit of short sea shipping.   Critical strategic issues relevant to formulating public policy are developed.  Coastal shipping has traditionally been a major sector of the maritime industry.  This continues to be the case in the European Union, but the sector has diminished in relative importance in North America as the transport industry has become increasingly dominated by less environmentally-friendly interstate trucking and railroads.  Congestion threatens to overwhelm overland carriage and limit economic growth.  An alternative strategy is to revitalize coastal shipping as short sea shipping to alleviate traffic congestion and enhance economic development by maintaining freight flow efficiency.  Because ship transport offers higher fuel economy and lower emission of harmful pollutants, the environmental benefits of short sea shipping over land transportation can be quantified and used to inform public policy.


Key words:  short sea shipping, fuel economy, ship operation cost estimate, hydrocarbon emissions, fuel consumption


1.  Introduction


This research establishes that substituting Short Sea Shipping (SSS) traffic for overland freight carriage in North America will result in significant alleviation of environmental impact in addition to offering a reduction in increasingly overburdened highway vehicular traffic.  SSS offers a possible solution in the form of an alternative transport mode as overland carriers have become overwhelmed and undependable due to traffic congestion.  The more successful SSS proves in achieving market share, the greater will be its impact in relieving clogged land arteries and lowering costs of transport over competing modes, as well as improving time performance.  More importantly, every mile a ton of freight is carried by SSS instead of by interstate truck lines or railroads will result in reduced fuel consumption and environmental impact.


SSS is used extensively to transport cargo throughout the European Union.  Although the United States once relied on coastal shipping lines, traditional coastal shipping has largely been supplanted by various kinds of overland transport, which consume more fuel and emit more pollutants that shipping.  Overland freight carriers now face the threat of paralysis due to economic expansion and population growth.  The short sea shipping concept is reviewed; the calculations for quantifying environmental impact are presented;  public policy implications are discussed; and a conclusion is presented.  Details of the hypothetical ship estimate are given in the appendix.

2.  Short Sea Shipping


The movement of cargo by sea is an important component of the European Union’s transportation system.  The intra-European Union sea movement of cargo represents 42% of the bulk goods being transported[1].  Short sea shipping in Europe is viewed as essential to alleviate highway congestion and reduce environmental pollution[2]. 


The characteristics found in the transportation network for the U.S. domestic market are similar to domestic markets found in nations with advanced economies.  Most developed nations rely on a national highway system to carry cargo, even though this is among the most expensive and environmentally-polluting, resource-consuming, transport modes.  Due to the fact that increases in annual freight movements in the U.S. far surpass that of annual highway mileage construction, highway congestion has become a significant problem, as is apparent in terms of increased travel time.  Highway travel time also increases the social welfare cost due to resultant inefficiencies.  Freight movement inefficiencies are projected to increase dramatically as US highways “. . . experienced a doubling of vehicle miles traveled in the past twenty years while the total highway mileage has only increased by 1%.”  This general trend is expected to continue.  Projections for the next fifteen years indicate explosive growth in cargo transport measured in both freight tonnage and value[3].


Because SSS has to be implemented basically from scratch for North American markets, policy makers and the transportation industry face the challenge of developing an efficient and effective complement to the existing transportation system they inherit.  At the same time, the situation presents opportunities because the industry is not constrained by existing environmentally unfriendly practices or traditions, and can select from among the most environmentally friendly capital infrastructure.  The conceptual model (Figure 1) is offered to focus discussion and eventually enhance understanding concerning the short sea shipping concept as a commercially viable enterprise. 


Figure 1.  Short Sea Shipping Facilitating (+) and Inhibiting (-) Factors

(Source: Lombardo 2004[4])



The extent of congestion on the East-coast I-95 highway corridor and elsewhere needs to be quantified by intermodal segment and a reasonable process for estimating the additional monetary costs needs to be developed.  The quantification of the congestion/travel delay experience is a precondition for promoting awareness of short sea shipping as a potential solution, as well as allowing for meaningful cost-benefit analysis.  Thus one data requirement is point-to-point cargo volume and delay time for the interstate highway system and for railroads.  The economic feasibility of short sea shipping focuses on whether it can offer lower freight charges than overland carriage. 


Whether short sea shipping can avoid or mitigate delay times, either by bypassing or alleviating overland congestion will likely be secondary.  Nevertheless, bad as congestion is today, it can only get worse as international trade is projected to double within the next decade.   Additionally, some trade flows within the U.S. are projected to triple by 2020[5].  Such significantly increased demand for transportation services will likely support higher freight charges; however the overall policy goal must be to minimize transportation cost, thus contributing to the U.S. general advantage from higher productivity.


Short sea shipping can offer two potential benefits:


  1. SSS may be cost competitive with overland shipping.  To establish competitive costs, the estimated costs of short sea shipping transport (including profit) must be compared to the actual costs of overland shipping (also including profit).  In the most favorable outcome, it will turn out that short sea shipping can be offered with a higher profit margin than contemporary overland shipping.  However, its success will alleviate overland congestion, and thus would lower costs (increasing profits) in the competing overland sector.  Thus SSS's success would contribute to improving its competitors' profit margins.  Producers cannot be expected to choose short sea shipping unless it can be offered at rates competitive with those offered by overland shippers, or lower.


  1. SSS may alleviate the congestion/travel delay problem by bleeding off some of the cargo volume from the highways.  To some limited extent, ability to realize this second benefit would justify policy intervention even in the absence of any ability to achieve the first, and studies should acknowledge and explore this possibility.  However, it seems highly unlikely that significant utilization of any alternative shipping facility would occur unless it offers some clear benefit; e.g., of either cost or time saving.  If intermodal segments can be identified where short sea shipping can offer a clear and significant time advantage compared to overland transport, either around the clock or at certain times of day, then SSS can be competitive even if its costs require a higher price.  However, cost estimates must capture the cost of fuel consumption.  The faster the operational speed of the short sea shipping fleet, the more expensive to operate, the higher costs, and the lower profits.  Short sea shipping can only prove viable if (a) its operating costs are sufficiently low to enable pricing below overland shippers, or (b) it can match or improve on the freight availability time offered by interstate trucking.  This includes travel time, queuing, loading, and unloading, and in most cases should capture the fact that deliveries made after normal business hours cannot be utilized or processed by the customer until the start of the next business day.  Though water-borne carriage is traditionally slower than trucking, this advantage to trucking diminishes over weekends, on overnight service, and increasingly at morning and evening rush hours and other chokepoints.  Operating costs rise with ship speed, though to some extent, faster travel time justifies higher pricing.  Exploratory modeling must capture the impact of both factors and their interrelationship.


Short sea shipping may offer both cost and time advantages, and to the extent possible, should be implemented in a way which maximizes both advantages.  Infrastructure should be designed with significant excess capacity and with capability for expansion and flexibility.


Many maritime professionals, government officials and academicians suggest that vessels with speeds of 30 to 40 knots are necessary for short sea shipping to be competitive with overland transport modes.  This conjecture must be carefully evaluated[6].  One of the cost advantages of ships over trucks and trains (one figure cited is that ship transport is 23% less expensive[7]) is lower fuel consumption, which depends on relatively low speed.  Cost advantages and environmental benefits might be erased if short sea shipping is implemented with a fleet of high-speed vessels.


The following cost comparison may not hold at all or by as great a margin, for a high-speed fleet.  One 15-barge tow is equivalent to 870 trucks, according to the U.S. Maritime Administration's haul comparison[8].  Its energy consumption shows one gallon of fuel can move one ton the following distances: 514 miles by inland barge, 202 miles by rail, and 59 miles by truck.  Part of this advantage disappears if the ships are operated at higher speeds.


3.  Quantifying Environmental Impact

This section quantifies the environmental impact of a proposed short sea shipping service.  North America's coastal and inland shipping has largely been supplanted by railroad and interstate trucking, which are often more expensive than ship movement, and frequently have greater environmental impact[9].  Infrastructure costs for overland transport have grown to the point where overland network infrastructure cannot easily be expanded.  Highway construction in the U.S. costs approximately $32,000,000 per lane mile plus $100,000,000 per interchange[10].   The interstate highway system was originally authorized at 41,000 statute miles.  To construct a parallel system of roughly comparable extent, intended for trucks only, with two lanes in each direction, would cost approximately $5,248,000,000,000.  This amount ignores interchanges and is nearly one-half the annual U.S. GDP.


European Union data document significant energy consumption advantages for maritime transport, 0.12-0.25 mega-joules/km as opposed to 0.60 for rail and 0.70-1.20 for highway.  CO2 emissions are also lowest for maritime transport: 30g per ton/km versus 41g for rail and 207g for highways[11] (Commission of the European Communities 2001).


Becker, Burgess, and Henstra (2004) and Lombardo, Mulligan, and Guan (2004) find high speed ships, with their high fuel consumption and high environmental impact, would not be feasible for SSS.  Baird (2004) discusses conditions for establishing economic feasibility of high speed operation[12].  Because harmful emissions are directly proportional to fuel consumption, fuel consumption is a meaningful measure of environmental impact.  Based on a conservative hypothetical baseline RoRo vessel with an 80 trailer capacity (cost estimate data is presented in the appendix), fuel consumption is estimated as a function of operating speed, estimated required shaft horsepower, and Admiralty coefficient.  The Admiralty coefficient (Ac) is defined as a quadratic function of the desired operating speed s


Ac = 1.84 s2 - 139.96 s + 2791.50                                       (1)


Shaft horsepower (SHP) is estimated as a function of the desired operating speed, deadweight capacity d, and Admiralty coefficient


SHP = (d2/3s3)/Ac                                                     (2)


Substituting the formula for Admiralty coefficient, we find that estimated SHP depends only on design deadweight capacity and desired operating speed


SHP = d2/3s3/(1.84 s2 - 139.96 s + 2791.50)                                 (3)


The equation used to estimate fuel consumption (F) over a round trip is


F = (SHP x 2 x route length)/23.4s                                       (4)


or, substituting the expression for SHP in terms of s,


F = (d2/3s2 x route length)/11.7(1.84s2 - 139.96s + 2791.50)                 (5)


This equation allows us to estimate total fuel consumption at different operating speeds calling for a range of different-sized engines, all over different route lengths.  Table 1 provides  insights  as  to  fuel  consumption measured in gallons given the operating speed in knots, over route lengths ranging from 200 to 800 nautical miles, for operating speeds ranging from 5 to 40 knots, for a hypothetical monohull RoRo vessel with a capacity of 80 tractor-trailers.  It should be noted that fuel consumption is a linear function of the route length.  For example, at a given operating speed, fuel consumption doubles if the route length is doubled, and triples if the route length is tripled.


Table 1. Fuel Consumption as a Function of Operating Speed and Route Length.

(Source: Lombardo, Mulligan, and Guan 2004.  See note 13.)


Operating speed

Route length








5 kt








10 kt








15 kt








20 kt








25 kt








30 kt








35 kt








40 kt








Note:  Fuel consumption in gallons of bunker fuel.


Fuel consumption increases exponentially with the operating speed as shown in Figure 2; e.g., increasing operating speed by 50% increases fuel consumption by approximately 300%.  This suggests that, in addition to having dramatically heavier environmental impact, higher operating speeds proposed by some SSS advocates will also impose dramatically greater environmental impact and fuel costs.


To compare SSS with overland trucking, the estimated fuel consumption per nautical mile traveled is computed by this equation


F' = (d2/3s2)/11.7(1.84 s2 - 139.96s + 2791.50)                           (6)


which is simply the reduced expression for F (Equation 5) divided by the route length.  Fuel consumption per nautical mile traveled is independent of route length, and is an increasing function of speed, as shown in Table 2.


Table 2.  Fuel Consumption per Nautical Mile Traveled and Fuel Economy as Functions of Operating Speed.

(Source: Lombardo, Mulligan, and Guan 2004.  See note 13.)


Operating speed

Fuel consumption/nm

Nautical MPG

5 kt



10 kt



15 kt



20 kt



25 kt



30 kt



35 kt



40 kt




1.  Fuel consumption/nm measured in gallons of bunker fuel per nautical mile traveled.

2.  Nautical miles per gallon compares roughly to statute miles per gallon.  1 nautical mile = 1.15078 statute mile.  1 statute mile = 0.86898 nautical miles.  Exact conversion requires knowledge of alternative sea and land routes under comparison.


 A single SSS vessel carrying 80 tractor-trailers at 20 knots will only burn approximately four gallons of diesel fuel every mile (Table 2 and Figure 3).  This extremely modest level of fuel consumption has to be compared to the fuel that would be burned, not by a single tractor-trailer, but by all eighty.  The reciprocal of fuel consumption per nautical mile is miles traveled per gallon of fuel consumed (Figure 4).  These figures are also provided in Table 2.


If a single tractor-trailer realizes fuel economy equivalent to four miles per gallon, the eighty-trailer SSS vessel realizes the same level of fuel consumption when traveling at only about eight knots.  Although this is much slower, it must be kept in mind that the 80 trailer RoRo ship is carrying eighty times the cargo of a single tractor trailer.  Thus, the ship has better fuel economy and lower environmental impact as long as it operates at a speed which allows for fuel economy better than 1/80 of the fuel economy realized by tractor-trailers, which occurs at any speed below approximately 27 knots. 


SSS can thus contribute dramatically to improved environmental quality.  This improvement in environmental quality is not limited to the superior fuel economy characteristics SSS offers, but also results from the fact that reduced congestion on interstate highways will allow truckers to drive faster and realize better fuel economy.  Furthermore, the primary benefit is directly proportional to the number of tractor-trailers or TEUs which can be removed from the interstate highway system and moved by ship.




4.  Implications for Public Policy


Since SSS seeks to address two critical problems outside the maritime industry, traffic congestion and pollution, government subsidies may be justified, at least initially, as a public policy initiative.  In fact, due to superior fuel economy, SSS can be implemented without subsidies, and subsidizing SSS cannot, in and of itself, serve the public welfare.  If private owners cannot earn profits engaging in an activity, consumers do not sufficiently value that activity to justify its performance.  Various restrictive regulations impose higher operating costs on U.S. domestic shipping operators, which are passed on to consumers of transportation services.  Frankel (2004) estimates U.S. cabotage policy imposes $3 billion in direct costs, and an additional $6 billion in indirect costs, on the U.S. economy[13].  Environmental benefits justify reevaluating restrictive government regulation and weighing costs versus benefits.


There remain other spheres where the government can play a financial role.  The government can utilize SSS as a customer, taking advantage of cost savings and lowered environmental impact.  The government can utilize SSS to move the mail, defense equipment, and military units, bypassing potential bottlenecks in overland transportation networks.  The government can create a tax environment favorable to SSS operators and their customers, including but not limited to, permitting accelerated depreciation, tax rebates, and tax cuts.  An effort should be made to implement favorable tax treatment for freight service consumers in terms of granting tax rebates to users of SSS.


Because overland shippers, the potential customers of SSS, pay significant taxes and use fees, mostly to state governments, part of these taxes can be rebated.  The government can rebate fuel and vehicle use taxes to SSS customers, to reward them for reducing pollution and relieving congestion by switching from overland carriage.  Every mile a truck is carried over the SSS network translates roughly into one less mile traveled over the interstate highway system, with attendant reductions in fuel consumption and environmental impact.  Rebating highway and fuel taxes rewards truckers who utilize SSS for the role they would be playing in mitigating environmental impact, as well as lessening the congestion experienced by other truckers and personal autos using the interstate highways.  SSS can offer significant environmental benefits, which justifies some level of tax relief or other government incentives.


5.  Conclusion


The challenge facing short sea shipping is to develop a commercially viable business model for the Western Hemisphere and an enhanced business model for Europe.  The critical success factor for SSS is that it must facilitate cargo movement as an inexpensive, seamless component of an integrated, intermodal transportation system.  Alleviating the environmental degradation forced by a growing economy and population will be a significant side benefit.  Key considerations for implementing SSS include:







The technical data on estimated fuel consumption and fuel economy contained in this report can be used to educate public policy decision makers, environmentalists, and maritime industry professionals who need to develop a sophisticated understanding of SSS and its implications for preserving the environment.  The favorable appraisal of SSS's environmental impact suggests the concept will inevitably become a reality.  A successful short sea shipping program offers an opportunity to add value to a national or international transportation network and thus improve economic efficiency and ultimately the societal standard of living.



Appendix:  Basic ship cost estimate


The basic estimation methodology is due to Benford (1965, 1967) and Hunt and Butman (1995)[14].  The ship construction estimate starts with an assumed cargo size t, which in this case, is 80 tractor-trailers, each hauling standard 40 foot, two-TEU trailers on chassis.  The ship’s design deadweight capacity d is estimated as


Deadweight capacity d = 28.6t                                           (A1)


The ship’s length is estimated as


L = 240.17 + 0.1107d                                                 (A2)


Beam is estimated as

B = 88.315 – 0.0226L                                                (A3)


Depth of the ship, keel to gunwale height, is estimated as


D = 14.19 + 0.0255L                                                (A4)


Draft of the ship T, the part of the ship’s depth below the waterline, is estimated as


T = 8.8585 + 0.047B                                               (A5)


The Admiralty coefficient Ac, is a quadratic function of the ship’s operating speed s


Ac = 2791.5 - 139.96s + 1.84s2                                        (A6)



This enables us to estimate the required shaft horsepower SHP for the engines given deadweight capacity and Ac


SHP = 0.667(DWT)3/Ac                                             (A7)



Cubic number, a measure of the hull volume or capacity, is a function of length, beam, and depth


CN = LBD/100                                                      (A8)


The steel weight for the hull in long tons is estimated as


WH = 280(CN)0.9(0.675+ 0.5 + 0.7)(1 + 0.36 x 0.05 x LS/L)(0.00585 x (L/D – 8.3)1.8 + 0.939)                                                             (A9)


In this formula, the ratio LS/L, the ratio of the length of the ship's superstructure to the overall length of the hull, will be assumed to be one.


Then, the steel weight of the ship’s outfit is estimated from


WO = 25(CN/100)0.825                                         (A10)



The steel weight for hull engineering is estimated from


WHE = 43(CN/1000)0.825                                     (A11)



The steel weight of the engine and related ship’s machinery is estimated as


WM = 60(SHP/1000)0.50                                       (A12)


Then the ship’s estimated displacement is the sum of the steel weights and the deadweight capacity


Disp = d + WS + WO + WHU + WM                               (A13)


We assume a standard U.S. shipyard hourly labor rate of $16.50 because under the Jones Act, all SSS tonnage will be built in American shipyards, though allowing foreign competition would greatly lower the cost of ship construction.


Labor hours required for fabrication and construction are estimated from the equations given in the following table.


Table A1.  Labor Hour Estimation Formulae by Ship Component. 

Source:  Developed by authors.





MHH = 68,000(WH/1000)0.85


MHO = 20,000(WO/100)0.90

Hull engineering

MHHE = 5,100(WHE/1000)0.75


MHM = 25,000(SHP/1000)0.60


Then the total cost to complete that component of the ship is given by the following equations.


Table A2.  Total Cost by Ship Component

Material plus Labor Cost.  Source:  Developed by authors.





CH = 1800WH + $16.50(MHH)


CO = 14000WO + $16.50(MHO)

Hull engineering

CHE = 27000WHE + $16.50(MHHE)


CM = 6000WM + $16.50(MHM)


Total construction cost is simply the sum of the material and labor costs for each category, with 120% shipyard overhead added.  Thus the total labor and material costs are multiplied by 2.20.


Cost = 2.20(CH + CO + CHE + CM)                                   (A14)


Shipyard profit is estimated at 10% of the cost to the builder, so the price charged to the owner is 10% higher than the shipbuilder’s cost.  Due to financial and risk issues, the owner’s cost is assumed to be 5% higher than the actual price charged by the shipyard.


Owner’s cost = 1.05(1.10(2.20(CH + CO + CHE + CM)))               (A15)


Days per trip is computed as twice the route length, for a round trip, divided by the operating speed times twenty-four hours.  One day is arbitrarily added for turnaround time in port, which is a highly conservative assumption for SSS RoRo service.  Actual turnaround time should generate significant additional economies.


Days/trip = (2 x route length/speed x 24) + 1                       (A16)


Fuel expenses are the price per gallon of bunker fuel, then multiplied by the ship’s shaft horsepower times 0.33 times twice the route distance, divided by the speed, divided by 7.8:


Fuel cost = $bunkers(0.33SHP(2 x route length/s)/7.8)                    (A17)


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[2] Commission of the European Communities [CEC]: White Paper on Common Transport Policy (1992); 

CEC: Communication from the Commission on the Development of Short Sea Shipping in Europe – Prospects and Challenges. COM (1995) Final, (July 5); CEC: Commission Staff Working Paper:  Progress Report from the Commission Services following the Council Resolution on Short Sea Shipping of 11 March 1996.  SEC (97) 877, May 6, 1997; CEC: Green Paper on Sea Ports and Maritime Infrastructure (1997); CEC: The Development of Short Sea Shipping in Europe:  A Dynamic Alternative in a Sustainable Transport Chain – Second Two-yearly Progress Report.  COM (1999) 317 Final (June 29); CEC: White Paper on European Transport Policy for 2010:  Time to Decide.  COM (2001) 370 (September 12); CEC: Communication from the Commission:  Programme for the Promotion of Short Sea Shipping.  COM (2003) 155 Final (April 7); CEC:  Communication from the Commission to the Council, the European Parliament, the European Economic and Social Committee and the Committee of the Regions on Short Sea Shipping.  Brussels:  COM (2004) 453 Final (July 2); CEC: Commission Staff Working Paper Annex to Communication from the Commission to the Council, the European Parliament, the European Economic and Social Committee and the Committee of the Regions on Short Sea Shipping.  Brussels:  COM (2004) 875 Final (July 7).

[3] National Chamber Foundation: Trade and Transportation – A Study of North American Port and Intermodal Systems (2003); U.S. Federal Highway Administration, Department of Transportation: Total Combined Truck Flows.  Office of Freight Management Operations (2002).

[4] Lombardo, G.A.: Short Sea Shipping:  Practices, Opportunities and Challenges.  TransportGistics, Inc., White Paper Series, (May 19, 2004).


[5] Wykle, K.R.: Are major landside corridors reaching capacity? In: Journal of Commerce Short Sea Shipping Conference, (April 19-20, 2004), pp. 4-10.


[6] Baird, A.J.: Investigating the feasibility of fast sea transport services. In: Maritime Economics & Logistics. Vol. 6 (2004), No. 3, pp. 252-269; Becker, J.F.F., Burgess, A., Henstra, D.A.: No need for speed in short sea shipping. In: Maritime Economics & Logistics. Vol. 6 (2004), No. 3, pp. 236-251.

[7] Commission of the European Communities [CEC]: White Paper on European Transport Policy for 2010:  Time to Decide.  COM (2001) 370 (September 12).

[8] U.S. Maritime Administration, Department of Transportation:  Short sea shipping initiative.  <> (October 30).  Washington DC: US Department of Transportation, 2004; U.S. Maritime Administration, Department of Transportation: Short sea shipping initiative<>, (October 30).  Washington DC: U.S. Department of Transportation, 2004.

[9] Brooks, M.R., Frost, J.D.: Short sea shipping: a Canadian perspective. In: Maritime Policy & Management. Vol. 31 (2004), No. 4 (October-December), pp. 393-407.

[10] U.S. Federal Highway Administration, Department of Transportation: Typical Interstate System Cost per Mile. Document Route Symbol HNG-13 (March 21, 1997) Federal Highway Administration, Federal Aid & Design Division.

[11] Commission of the European Communities [CEC]: White Paper on European Transport Policy for 2010:  Time to Decide.  COM (2001) 370 (September 12).

[12] Becker, J.F.F., Burgess, A., Henstra, D.A.: No need for speed in short sea shipping. In: Maritime Economics & Logistics. Vol. 6 (2004), No. 3, pp. 236-251; Lombardo, G.A.; Mulligan, R.F.; Guan, C.Q. US Short Sea Shipping:  Prospects and Opportunities.  Report prepared for the Short Sea Shipping Cooperative, Washington, D.C. (November 1, 2004).  Kings Point, New York: Center for Maritime Studies, U.S. Merchant Marine Academy; Baird, A.J.: Investigating the feasibility of fast sea transport services. In: Maritime Economics & Logistics. Vol. 6 (2004), No. 3, pp. 252-269;

[13] Frankel, E.: Rules and Economic Impact of U.S. Cabotage (Jones Act) Laws. International Association of Maritime Economists (IAME) conference. Izmir, Turkey (30 June - 2 July, 2004).

[14] Benford, H.: General cargo ship economics and design. Ann Arbor, Michigan: University of Michigan, 1965; Benford, H.: The Practical Application of Economics of Merchant Ship Design.  In: Marine Technology, The Society of Naval Architects and Marine Engineers (January) 1967; Hunt, E.C., Butman, B.S.: Marine Engineering Economics and Cost Analysis. Centreville, Maryland: Cornell Maritime Press, 1995.