The store by me is still at 50%, I know last year they did take the Christmas lights to 75%, I don't ever recall them doing 90% but perhaps it does depend on having the room to store it. My store has 2 rows for all clearance stuff, it still has lawn and garden stuff at 50% off.
Our store sometimes has the coupons for an extra 20% off-that is when I find you can get really good deals. Last year they had a Sunbeam Heritage Mixmaster that retails for about 125. and I got it for 25.