Countdown to Christmas. Perpetual Flip Calendar. Christmas day is the most fun day of the year and looking forward to it is even more exciting. Count the weeks until Santa next squeezes down your chimney bearing special gifts. 1 page for each week with big bold numbers, 52 pages cleverly designed to be re-used year after year in endless anticipation of Dec 25th and all the associated presents, parties, feasts and novelty socks.