This screener lists stocks that currently match DEMA(7) Crossed Below DEMA(200), one of the Double Exponential Moving Average Crossovers screens. The key difference between a double exponential moving average (DEMA) and an EMA is that a DEMA is calculated using two EMAs, one for the price data and one for the smoothed data. The list is updated daily: open a chart for any ticker, or customize the screen, set an alert and backtest it as a trading strategy.
