Why all the closings?

CNNMoney.com has an article on why so many stores are closing branches, citing many of the recent closings that we've discussed here. The article is worthwhile, but basically it comes down to two points:

• There are too many stores -- 19.5 square feet of retail per capita
• Online is cutting into sales -- up 22% in 2005 to $143b (although it is also pointed out that that is still only about 2% of total retail)