When Bear Stearns Cos. was collapsing in early 2008, U.S.officials struggling to contain the damage feared fallout from thebank's derivatives trades could devastate already roiling markets.But they couldn't tell how bad things could get, or who would behit the hardest, because at the time banks didn't have to reportthe details of their swaps transactions.

Nearly a decade later, the regulator in charge of overseeing the$483 trillion global swaps market says it still often initiallygets only a murky view of those transactions. That's in partbecause the rules devised to solve the problem have created apatchwork system where data is collected under different formatsand standards. As soon as this week, Commodity Futures TradingCommission acting chairman J. Christopher Giancarlo aims to changethat by announcing an effort to rewrite the rules to make the datamore usable.

The way it works now, four privately owned data repositories,approved by the government, collect and report data on the swapsmarket. In the absence of thorough guidelines, they are allowed touse different standards that leave it to CFTC workers to cobbletogether a full picture of systemic risk. The goal of the agency'snew effort will be to standardize the data.