20 Day Breakout Indicator

Hi, I am looking for a 20 Day breakout indicator. (the high/low of the extreme for the past 20 days)

Can anyone help me find one or make one? I like it so that the breakout bars are marked by arrows above or below the bars.

Search for Donchian Channel, should be several threads with the indicator. I'll see if I can dig one up.

Here's one. I think you can set any number of days you want.

thanks for the indicator, i think this is even better than what i have asked for. but what does the margin and extreme values represent?

Sorry, don't know.

Thanks for indicator.