The COT Report is very useful since it provides details into how traders are positioned in various markets. Unlike sentiment surveys, the COT Report represents actual money. This indicator demonstrates how non-commercials (a.k.a. large speculators) are positioned in this market. Large speculators are typically trend followers: they buy as prices rise and sell as prices fall.
Data source: CFTC (Commodities Futures Trading Commission)
Chart software: HighCharts