The Relative Momentum Index (RMI) was developed by Roger Altman. Impressed with the Relative Strength Index's sensitivity to the number of look-back periods, yet frustrated with it's inconsistent oscillation between defined overbought and oversold levels, Mr. Altman added a momentum component to the RSI. As mentioned, the RMI is a variation of the RSI indicator. Instead of counting up and down days from close to close as the RSI does, the RMI counts up and down days from the close relative to the close x-days ago where x is not necessarily 1 as required by the RSI). So as the name of the indicator reflects, "momentum" is substituted for "strength".
You can change long to short in the Input Settings WARNING: - For purpose educate only - This script to change bars colors.