After a series of historic lows, the American Institute of Architects' Architecture Billings Index (ABI) was up more than eight points in March. 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 March ABI rating was 43.7, up from the 35.3 mark in February. This was the first time since September 2008 that the index was above 40. The score still indicates an overall decline in demand for design services (any score above 50 indicates an increase in billings). The new projects inquiry score was 56.6. “This news should be viewed with cautious optimism,” said AIA chief economist Kermit Baker. “The fact that inquiries for new projects increased is encouraging, but it will likely be a few months before we see an improvement in overall billings.”