TRIX was created by Jack Huton. It is a momentum indicator that displays the percent rate-of-change of a triple exponentially smoothed moving average of a security's closing price. It  it is designed to filter out price movements that are considered insignificant or unimportant. The indicator can be used to anticipate turning points in a trend through its divergence with a security's price.

Custom PCF Formula

Where x is the period which must be an integer.

100 * (XAVG(XAVG(XAVGCx, x), x) / XAVG(XAVG(XAVGCx.1, x), x) - 1)


A 15 period TRIX can be written as follows.

100 * (XAVG(XAVG(XAVGC15, 15), 15) / XAVG(XAVG(XAVGC15.1, 15), 15) - 1)

Read more about Triple Exponential Average (TRIX) at Investopedia