Open Interest.

The open interest in a security for a given interval.

Syntax:
OpenInterest(Interval, [Ref], [Symbol]). Intervals can be D, W, M or Q only.

Interval = Required. 

[Ref] = Optional.

[Symbol] = Optional.

Examples:

OpenInterest(D,,YHOO)

The open interest in YHOO for the last Day.

OpenInterest(W,,)
The open interest in the security on the current line for the last Week.