The following is the Congressional Budget Office An Analysis of the Navy’s Fiscal Year 2017 Shipbuilding Plan which was released on Jan. 4, 2016.
From the report:
CBO Estimates That Spending for New Ships in the Navy’s Plan Would Average $18.9 Billion per Year
The Navy estimates that buying the new ships specified in the 2017 plan would cost $509 billion (in 2016 dollars) over 30 years, or an average of $17.0 billion per year—slightly more than the amount that the Navy estimated the construction of new ships would be under its 2016 plan. Using its own models and assumptions, CBO estimates that those new ships would cost a total of $566 billion (in 2016 dollars) over 30 years, or an average of $18.9 billion per year.