Quote from ak15:
The other major advantage of claiming MTM is that you can carry forward or back your net operating loss for losing years and offset them against net operating gains in future years. As an example if you had a NOL of $50,000 in 2008 and a net operating gain of $40,000 in 2009, you will offset the $40,000 NOG against the $50,000 NOL and not pay any taxes in 2009. Furthermore, you get to carry over the excess of $10,000 NOL to 2010 and assuming you have a NOG in 2010, can offset this gain against the $10,000 remaining NOL excess.