Should work in earlier than SS 6179,
if red: will have to be doctored.

X_Y Plot wisely rich plot.sm (93.36 KiB) downloaded 716 time(s).

Wrote

Should work in earlier than SS 6179,
if red: will have to be doctored.

NO, should work in later than SS 6179.
Though the polyfit looks good, here is better model.

X_Y Plot wisely rich plot.sm (101.5 KiB) downloaded 668 time(s).