A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Defense (DOD) 2012 portfolio of 86 major defense acquisition programs is estimated to cost a total of $1.6 trillion, reflecting decreases in both size and cost from the 2011 portfolio. Those decreases are largely the result of more programs exiting than entering the portfolio, as well as reductions in procurement quantities due to program cancelations and restructurings. Notably a majority of programs in the portfolio gained buying power in the last year as their acquisition unit costs decreased. DOD's 10 costliest programs, excluding the Missile Defense Agency's Ballistic Missile Defense System (BMDS), drive most of the portfolio's cost performance and funding needs. The majority (65 percent) of the funding that DOD estimates it will need to complete its current programs is associated with those 10 programs, and almost all of that funding is for procurement."