Following consistently increasing demand for design services throughout most of 2013, the Architecture Billings Index (ABI) has posted its first consecutive months of contraction since May and June of 2012. As a leading economic indicator of construction activity, the ABI reflects the approximate nine to twelve month lead time between architecture billings and construction spending. The American Institute of Architects (AIA) reported the December ABI score was 48.5, down from a mark of 49.8 in November. This score reflects a decrease in design services (any score above 50 indicates an increase in billings). The new projects inquiry index was 59.2, up from the reading of 57.8 the previous month.