The U.S. hotel pipeline continues to drop, according to May's STR/McGraw Hill Construction Dodge Pipeline Report, released yesterday. The 310,762 rooms under development represent a 3.6 percent year-over-year dip. Noteworthy, however, are the South and Mid-Atlantic regions, which account for 40 percent of the rooms under construction. In the more speculative pre-planning phase, the Mountain and South Atlantic regions led the way. On the flip side, three regions reported decreases of more than 30 percent of rooms under construction: the West South Central (-54.5 percent), the Pacific (-33.8 percent) and New England (-32.9 percent).