Information about the Commercial Index of Larry Williams (WillCo) and how to calculate it


Example image of Commitments of Traders (CoT) chart of Williams-Commercial-Index for gold on CME

The Williams Commercial Index, also known by the short name WillCo Index, was developed by Larry Williams to analyze the positioning of commercials on the futures markets. Unlike the CoT index weighted the WillCo index relative to the overall market. For this, the net position of a market participant is initially divided by the total Open Interest at the time of the respective net positon. In order to calculate the oscillator, these data will be used in the following as in the CoT index set in ratio to the highs and lows within a selectable period. As default 26 weeks were chosen here. This corresponds to the period proposed in the books of Larry Williams.

For the Williams Commercial Index, calculate the quotient for each week:

Q =  
Net-Position

entire Open Interest

These are then used to calculate the oscillator:

Q of the current week - Minimum Q of last n weeks

Maximum Q of last n weeks - Minimum Q of last n weeks