Yesterday I showed the strong seasonal tendency of the SPX on the 1st trading day of May. One reader wrote and asked whether the day-1 strength exhibits a tendency to follow through or to reverse. I took a quick look and was surprised at how consistent the results were. You may find them in the table below.
Of the 17 instances that rose on the first day in May since 1987, 13 of them closed lower 4 days later.