Definition. The OHLC data for the US500 index, a broad U.S. stock market index tracking the performance of 500 leading large-cap companies listed in the United States.

Technical. On non-trading periods (weekends, market holidays, and outside market hours for intraday resolutions), OHLC values are forward-filled from the last trading session's close price. Daily resolution has data since January 2009. Intraday resolutions (10m, 1h) have shorter history.