Cumulative Tick Indicator

[Longscalper]

I am interested in an indicator for Tradestation that will do the following:

Have a running 13-period total of half-hourly Nasdaq or NYSE TICK readings. The TICK readings, of course, show the number of issues which last traded on an uptick minus those which last traded on a downtick.

I would like to place this indicator in a sub graph or in its own chart window to observe the overbought/oversold conditions when this indicator shows extreme readings.

Does this indicator currently exist or would an existing indicator need to be modified, or a must a new indicator be written?

Thanks for any info and help.