Sell in may? Last five years

[#1]

Investors Daily Edge has this ifo for last five years for 1 June to 1 Sept. It says: As you can see, the market goes virtually nowhere between June 1st and Sept. 1st. The moves each year were as follows: 2004: -3.3% 2005: -0.08% 2006: 1.8% 2007: -1.6% 2008: -7.8%