A technical analysis indicator, developed by P.N. Haurlan, that is used to detect market breadth. There are three components of the Haurlan index:

Short Term: a 3-day exponential moving average is taken of the net NYSE advances over declines.

Intermediate Term: same, using a 20-day exponential moving average.

Long Term:same, using a 200-day exponential moving average.
Each of the three components is used to detect a different movement, whether it is momentum, breakouts, or resistance.