Stocks with predictable cycles are gold if you have enough money to take advantage of the obvious-but-small fluctuation and to take the hit when they occasionally skip a cycle. In the case of NutriSystem (NTRI), there is the dividend buffer to help the bad calls. Still, not something to buy during New Years resolutions or pre-bikini season. The start of the school year and pre-holidays though? Keeping an eye out for a dip.