CRS report via FAS – High Frequency Trading: Overview of Recent Developments, Rena S. Miller, Specialist in Financial Economics; Gary Shorter, Specialist in Financial Economics, April 4, 2016.

“High-frequency trading(HFT) generally refers to trading in financial instruments, such as securities and derivatives, transacted through supercomputers executing trades within microseconds or milliseconds (or, in the technical jargon, with extremely low latency). There is no universal or legal definition of HFT, however. Neither the Securities and Exchange Commission (SEC), which oversees securities markets, nor the Commodity Futures Trading Commission (CFTC), which regulates most derivatives trading , have specifically defined the term. By most accounts, high frequency trading has grown substantially over the past 10 years: estimates hold that it accounts for roughly 55% of trading volume in U.S. equity markets and about 40% in European equity markets. Likewise, HFT has grown in futures markets—to roughly 80% of foreign exchange futures volume and two-thirds of both interest rate futures and Treasury 10-year futures volumes. The CFTC oversees any HFT, along with other types of trading, in the derivatives markets it regulates. These include futures, swaps and options on commodities, and most financial instruments or indices, such as interest rates. The SEC oversees HFT and other trading in the securities markets and the more limited securities-related derivatives markets which it regulates..”