The name "Black Friday" is from accounting, which uses black to signal profit and red to signal loss. Black Friday has been the unofficial beginning of the Christmas season since the 1930's. In fact, President Roosevelt moved Thanksgiving up a week during the Great Depression because retailers wanted an extra week of shopping revenue. This pleased retailers, but irritated shoppers, who had to change plans. This year, Black Friday is especially important. It will signal whether the recession will continue to hurt retailers, since 18% of retail sales occur from Black Friday through Christmas. This year, the National Retail Federation is projecting a 1% decline, which is up a bit from last year's drop of 3.4%.