Kathryn Watson of the Daily Caller highlights an alarming lack of oversight associated with federal government credit cards.

Federal employees are buying more with government credit cards than ever, but Americans don’t know how much of the billions of tax dollars being spent annually is legitimate versus what is lost to waste, fraud and corruption.

“We’ve been tracking this issue for years, and that’s why it’s unfortunate that it just doesn’t seem to go away,” Scott Amey, general counsel for the nonprofit Project on Government Oversight (POGO), told The Daily Caller News Foundation.

A widely read report earlier this month detailing a top Pentagon aide’s use of his government credit card at foreign strip clubs highlighted how egregious abuses still plague the federal government. But waste, fraud and corruption can be difficult to catch when credit card spending is so high.

An estimated 261,000 federal employees spent $19 billion using government-issued credit cards in fiscal year 2015, up from 2014’s 263,000 employees spending $17.1 billion, and the most since that kind of spending reached $19.5 billion in 2011, according to the credit card-managing General Services Administration (GSA).

That’s more than enough to buy the five most valuable NFL teams, worth a combined $16.65 billion, and more than twice as much as the $8.4 billion the National Retail Federation expects Americans to spend on Halloween this year.

But efforts to strengthen oversight — like the Government Charge Card Abuse Prevention Act introduced by Iowa Republican Sen. Chuck Grassley and passed in 2012 — haven’t required the federal government to calculate how much is lost to waste, fraud and abuse.