[description=A moving average indicator developed by Richard Donchian.]
[target=Price; category=Bands; author=Donchian, Richard]
n := input("Time periods",20,1);
[name=Top;linestyle=solid]
upper := hhv(H,n);
[name=Middle; linestyle=dash]
middle := (hhv(H,n) + llv(L,n))/2;
[name=Bottom;linestyle=solid]
lower := llv(L,n);
{Fill}
[name=Upper Fill; linestyle=fill; color=cyan]
upper; middle;
[name=Lower Fill; linestyle=fill; color=yellow]
middle; lower;
[name=Top;linestyle=solid]
hhv(H,n);
[name=Middle; linestyle=dash]
(hhv(H,n) + llv(L,n))/2;
[name=Bottom;linestyle=solid]
llv(L,n);