instead of using 20,2 and 20,1 I tried 20,2 and 20,1.618.
Many TWEAKS are possible.Basically these are dependent on the volatility on
particular day.Perhaps on a very flat day instead of BB(20,2) and BB(20,1)
,You can as well try BB(20,1.6) and BB(20,0.8) ,thereby narrowing the bands.