// Downloaded From https://www.WiseStockTrader.com
periods = BarIndex() - SelectedValue(BarIndex());
trv = Param("Trailing", 2, 0.2, 150, 0.01);
graph = IIf(periods > 0, HHV(High, periods) - trv, Null);
trc = ParamColor( "Trail Color", colorCycle );
Plot(graph, "Trail", trc, 8);