Office Depot has reduced the total square footage of its North American Retail Division to 25.33 million square feet at the end of 2012, down from 30.67 million square feet at the end of 2008 -- a 17% reduction. In merger-related documents filed with the U.S. Securities 7 Exchange Commission, the retailer said it is not done shrinking yet and may have two to three more years of downsizing ahead of it.