For US equities as a whole, May has been a pretty good month with the average S&P 500 stock rising nearly 1%. In terms of individual stocks, though, there have been a number of standouts. The table below lists the 17 stocks in the index that have rallied over 15% this month. Topping the list of winners is Micron (MU). Of the 21 trading days so far this month, the stock has been up on 16 of them for a total gain of 40%. Besides MU, a number of retail-related stocks made the list of biggest winners including Tiffany (TIF), Foot Locker (FL), Ralph Lauren (RL), Under Armour (UA and UAA), and Lowe’s.

Below is a list of the biggest losers in the S&P 500 so far this month. Just as a tech stock tops the list of biggest winners, another one (Symantec – SYMC) tops the list of losers.  Besides SYMC, other notable names include old-time brands like Campbell (CPB), Molson Coors (TAP), Xerox (XRX), and Newell (NWL).

On a final note, not only is Micron the biggest winner this month, but it is also having one of its best months in years. The chart below shows the monthly performance of the stock over the last thirty years. With a gain of 40%, MU is having its best month since December 2009 and its 8th best month over the last thirty years.