The Commitments of Traders (COT Report) has several key terms you need to understand before you can read the report. The key terms are, Open Interest, Reportable Positions, Commercial and Non-commercial Traders, Non-reportable Positions, Spreading, Changes in Commitments from Previous Reports, Percent of Open Interest, Number of Traders, Old and Other Futures, Concentration Ratios, and Supplemental Report.
Number of Traders – To determine the total number of reportable traders in a market, a trader is counted only once regardless of the trader appearing in more than one category.
(non-commercial traders may be long or short only and may be spreading; commercial traders may be long and short).
To determine the number of traders in each category. However, a trader is counted in each category in which the trader holds a position.
Which means, the sum of the numbers of traders in each category will often exceed the “Total” number of traders in that market.