What It Means
Change in OI is the difference between a strike's Open Interest right now and its Open Interest at the previous session's close — a positive number means more contracts were opened than closed today, a negative number means the opposite. It's shown as its own column on the option chain, separate from the raw OI figure.
Example
If Nifty's 24,100 Call closed yesterday with 20 lakh contracts of Open Interest and today's chain still shows 20 lakh OI, even with 8 lakh contracts of Volume traded, Change in OI reads close to zero. Heavy activity, but no net new positions left open. If OI instead shows 27 lakh, Change in OI reads +7 lakh: real new positions built up today.
Warning
A large Change in OI number on its own doesn't say which direction the market is headed, only that positions are moving. Pair it with price direction (see Long Buildup, Short Buildup, Short Covering, and Long Unwinding) before reading it as bullish or bearish.
Related Terms
- Open Interest (OI) — the raw figure this column is the daily delta of
- Long Buildup — one of the four patterns built from this number
- Short Buildup — another of the four patterns built from this number