From the link:
How important is long-term breadth to the swing trader?
It is a trigger to get into the trade and an answer to one of the most difficult questions in market timing and stock trading — When to get out?
Measured here by the McClellan Summation Index ($NYSI), this latest upswing began on the open of of 8/20 and closed on the open today, a 10-trading-day swing. See the indicator in the center band of the charts below).
For the profit results for the swing trade: