RVI ,Finding Bottom and Top

I added a bollinger band to rvi, so we know the upper and lower limits of rvi, and in my opinion the results are satisfactory,

When rvi is below the lower bollinger the indicator will change color to green which indicates a buy signal and vice versa,

But we also have to be careful with changes trends, volume analysis will be helpful for determining the bottoms and top of price movements,
I recommend using this indicator when the price is above MA 200