One sole analyst oversees the entire market for crude oil derivatives thanks to tight budgets, a top federal regulator testified Tuesday.

"We have one analyst on crude oil," said Timothy Massad, the chairman of the Commodity Futures Trading Commission tasked with regulating derivative contracts. "Now, crude oil has been subject to incredible volatility, but that's because we simply cannot afford to have more people on that."

Massad made his remarks at a Senate hearing on appropriations for his agency, which he argued has been underfunded by Congress.

"If our budget is flat, we cannot even maintain what we're doing today" in terms of surveillance of markets, he testified.

The agency, which has roughly $250 million in funding, has 50 staffers in surveillance, Massad said. Those analysts must oversee 40 markets for physical commodities, in addition to all the financial futures products.

"For a lot of the [agriculture] products, we don't even have one person," Massad said.

The Obama White House asked Congress to boost the agency's funding to $330 million in fiscal 2017. Massad said he would like to increase the surveillance staff by 50 percent.

Congressional Republicans, however, have generally opposed increasing funding for the CFTC and other financial regulatory agencies, faulting them for failing to prioritize and for straying from their core tasks. On Tuesday the head of the approprations subcommittee before which Massad appeared also raised concerns with the agency's spending on leases.