Skirt Length Theory
The theory is that if the skirts that are being worn by women are short then we are in an exuberant, buoyant bullish market. If the skirts are long then the outlook and current market direction is bearish.
Although this is an entertaining theory, nobody has ever been able to provide empirical proof of the relationship of skirt length to market direction.
The "Short Skirt Indicator" would be considered an Economic Indicator.