In 2009, Group of 20 leaders agreed to overhaul rules governing the over-the-counter derivatives market, including a requirement to report all OTC derivatives to trade repositories. The rule was intended to help regulators detect systemic risk. However, logistics have been more challenging than expected. "There are 18 trade repositories globally -- how do regulators access all that data?" said Marisol Collazo of Depository Trust & Clearing.