U.S. hoteliers added 38,409 new rooms to their inventories in 2011 -- about half of the 75,747 rooms that were expected as of December 2010, according to STR Global. The most recent STR/McGraw Hill Construction Dodge Pipeline Report showed that the 373 properties that were to open stateside in 2011 represented a 0.5 percent increase in the existing room supply. The Upper Midscale segment was responsible for the most new rooms (15,579), a 36.6 percent increase over 2010. The Upscale segment followed, with 8,557 new rooms. New Luxury segment rooms represented the smallest portion, with 1,261. STR points to a potential pickup in new supply over the coming years. For 2012, 649 properties are expected to debut, for a total of 70,291 rooms. Again, the Upper Midscale segment is seeing the most activity, with 24,269 rooms anticipated.