The SPX has had a pattern over the past two years, it moves in periods of an average 17 weeks, If this pattern will hold then we should get to the low of the present cicle  by options expiration in June, You can measure it in a weekly chart going back the entire Bear Mkt. Starting from the March lows and depending on how you count the weeks we are now in the 13th week of the present cycle... Interesting how the bear mkt has been very tidy.