1W Change in Future OI is calculated as percentage change in OI between 5 trading days. Suppose the open interest (OI) position on Friday is 100 and on last Friday it was 170, 1W change in OI is calculated as (170/100) – 1*100 = 70%. A positive output indicates rising number of OI’s whereas a negative output indicates drop in OI’s.
As a rule of thumb, if the spot price of the stock and OI of futures both move up, it indicates a bullish signal and prices might continue to rise. A decrease in price with an increase in OI or conversely an increase in price with a fall in OI both indicates bearish signal.