After stepping back in October, reversing into the negative territory, the Architecture Billings Index (ABI) rose more than three points in November to reach its highest mark since December, 2007. As a leading economic indicator of construction activity, the ABI reflects the approximate nine-to-twelve-month lag time between architecture billings and construction spending. The American Institute of Architects (AIA) reported the November ABI score was 52.0, up from a reading of 48.7 the previous month.