AverageDirectionalMovementIndex

Commonly abbreviated as ADX.
Is a trend indicator.
Is computed using the high, low, and close prices.
Returns one time series, which is a 14-period Wilder's moving average of Directional Movement Index.
FinancialIndicator["AverageDirectionalMovementIndex",n] uses a period n moving average.
The first value in the time series occurs after periods.