How Has The Defense Department Spent Funds Training Syrian Rebels?

How much has the United States spent to train the force of 60 Syrian rebels to take on the Islamic State?
According to basic math, about $4 million for each of them.
Fortunately for a program that calls into concert logistics travelling half-way around the world to equip and train guerrilla fighters, basic math does not sufficiently draw a picture of cost-analysis.
Reported by POLITICO, $500 million was requested last year for the program, roughly half has been spent.