It seems like today is one of Whole Food's worst days, with their shares suffering a 19.7% drop, reaching $38.51 this morning. Their shares fell due to worst outlook for the year and lower same-store sales. The worst day before now was back in 2006 when it dropped 23%. Apart from these two times, the stock had seen bigger drops in Jan 1999 and Aug 1998. We can see now that Whole Foods is very volatile around earning releases. Hopefully they will be able to recover again.