Automatic exercise
The automatic exercise of options that finish in the money on the expiry date.
How to read the number
No instruction is needed: the exchange itself exercises whatever carries intrinsic value, under the rules of the specification.
When the metric lies
It fires even when the holder would rather it did not: the next morning a futures position with its collateral is sitting in the account, to be closed at whatever prices the new session brings.
Also known as: auto-exercise