Vessel Count, Dispositions, Acquisitions and Construction Programs  Vessel Dispositions The average age of the company's 377 owned or chartered vessel fleet at March 31, 2010 is approximately  17.8 years. The average age of the 170 newer vessels that the company acquired or constructed since  calendar year 2000 as part of its new build and acquisition program (discussed below) is approximately  5.4 years. The remaining 207 vessels have an average age of 28.0 years. The following table compares the  average number of vessels by class and geographic distribution during the years ended March 31 and the  actual March 31, 2010 vessel count: Included in owned or chartered vessels are vessels that were stacked by the company. The company  considers a vessel to be stacked if the vessel crew is off hire and limited maintenance is being performed on  the vessel. The company reduces operating costs by stacking vessels when management does not foresee  adequate marketing possibilities for the vessel in the near future. Vessels are added to this list when market  conditions warrant and they are removed from this list when they are returned to active service, sold or  otherwise disposed. When economically practical marketing opportunities arise, the stacked vessels can be  returned to service by performing any necessary maintenance on the vessel and returning fleet personnel to  operate the vessel. Although not currently fulfilling charters, stacked vessels are considered to be in service  and are included in the calculation of the company’s utilization statistics. The company had 83, 61 and 53  stacked vessels at March 31, 2010, 2009 and 2008, respectively. The vast majority of vessels stacked at  March 31, 2010 are currently being marketed for sale and are not expected to return to the active fleet,  primarily due to their mature age. Vessels withdrawn from service represent those vessels that management has determined are unlikely to  return to active service and are currently marketed for sale. Vessels withdrawn from service are not included  in the company’s utilization statistics. The company seeks opportunities to sell and/or scrap its older vessels when market conditions warrant and  opportunities arise. The majority of the company’s vessels are sold to buyers who do not compete with the  company in the offshore energy industry.  Fiscal 2010 . The company disposed of 70 vessels in fiscal 2010, including 25 anchor handling towing  supply vessels, 21 platform supply vessels, 10 crewboats, seven offshore tugs, five utility vessels and two  other type vessels. Five of the 70 vessels disposed of were from the U.S. GOM vessel fleet while 61 vessels  were from the international fleet. The remaining four vessels were disposed of from vessels previously  withdrawn from service. Six of the platform supply vessels that were disposed of were sold and leased back  by subsidiaries of the company during fiscal 2010. A complete discussion regarding the sale/leaseback  transactions is disclosed in the Note 9 of Notes to Consolidated Financial Statements. -46-  Actual Vessel Average Number   Count at  of Vessels During  March 31,  Year Ended March 31,  2010 2010 2009 2008 International-based fleet: Deepwater vessels 50 44 33 30 Towing-supply/supply 201 206 224 222 Crew/utility 61 67 71 71 Offshore tugs 27 26 33 37 Other --- --- 3 5 Total 339 343 364 365 United States-based fleet: Deepwater vessels 8 6 7 7 Towing-supply/supply 23 26 32 36 Crew/utility 7 7 11 13 Total 38 39 50 56 Owned or chartered vessels included  in marine revenues  377  382  414  421  Vessels withdrawn from service  7  8  15  23  Joint-venture and other 10 10 13 14 Total 394 400 442 458