Financial management at the Pentagon is laughable

The Pentagon can't do simple bookkeeping.  For example, in fiscal 2011 it made $238.2 million in overpayments and $48.4 million in underpayments related to travel alone. But documentation of these payments sucks; the Pentagon was only able to identify $1.6 million, or less than 1 percent, of the program's estimated overpayments as recoverable, explaining that they lacked supporting documentation.  Documentation is so bad that the GAO can't validate many purchases.
 
Overpayments are not a new problem. In the 1990s, the Army paid $6 million to 2,269 troops who had already quit the service, were absent without leave or had deserted their units.The Army was able to document one overpayment since 2009, it was for the huge sum of $20.79.

Some at the Pentagon should go back to grammar school as the department claimed it would recover $67.6 million in improper military retirement payments while estimating that only $18.8 million in overpayments had actually occurred.  It's magic!