The TRIX indicator was developed in the early 80s by Jack Hutson and displays the one day percentage change of a TRIple smoothed eXponential average of the Close Price.
By smoothing the averages the indicator can filter volatile price changes without too much lagging.
It is usually combined with a 9 day EMA of the TRIX line. These 2 lines can be analyzed for crossovers.
1. calculate 15 day EMA of the Close Price
2. calculate 15 day EMA of 1
3. calculate 15 day EMA of 2
4. TRIX = 1 day percentage change in 3