An implementation of the "Coppock Unchanged" plot concept by Tom McClellan.
Simply put, assume that for each bar, an alternative close creates a Coppock Plot that is unchanged, i.e. a close that generates a flat coppock curve.
This coppock unchanged plot can be used to: 1) identify a start of a trend on a long timescale (monthly) when the price goes above the coppock unchanged plot after a major correction 2) potentially identify an end of a trend when the prices goes below the coppock unchanged plot
See Tom McClellan's article 'Coppock Curve Still Working On a Major Bottom Signal' for a full explanation...