The following is an April 24, 2017, Congressional Budget Office report, “Costs of Building a 355-Ship Navy.”
From the Document:
In December 2016, the Navy released a new force structure assessment (FSA) that called for a fleet of 355 ships—substantially larger than the current fleet of 275 ships and also larger than the Navy’s previously stated goal of 308 ships.1 In response to a request from the Subcommittee on Seapower and Projection Forces of the House Committee on Armed Services, the Congressional Budget Office has estimated the costs of achieving the Navy’s objective within 15, 20, 25, or 30 years. As part of its analysis of those alternatives, the agency assessed the implications of building and operating a 355-ship fleet, including the number of ship purchases that would be necessary, prospective inventory levels, personnel requirements, and effects on the shipbuilding industry.
To enlarge the Navy to 355 ships would require a substantial investment of both money and time. CBO estimates that the earliest the Navy could achieve its goal of a 355-ship fleet would be in 2035, or in about 18 years, provided that it received sufficient funding. However, the cost to build and operate a 355-ship fleet would average $102 billion per year (in 2017 dollars) through 2047, CBO estimates, or more than one-third greater than the amount appropriated for fiscal year 2016 for today’s 275-ship fleet. On average under CBO’s alternatives, shipbuilding costs would be at their highest point over the next 10 years, while operating costs would be highest between 2037 and 2047, once the fleet numbered 355 ships.