The AIA’s monthly Architecture Billings Index recovered from a dip into negative territory last month by crossing the break-even threshold in February with a score of 50.3, reflecting a slight increase in design services for the month. That’s up from January’s contraction in billings, yielding an index score of 49.6. The ABI is a leading economic indicator of construction activity in the U.S. that reflects the nine- to 12-month lead time between architecture billings and construction spending nationally and regionally as well as by project type. Marks above 50 indicate growth in billings for the period while those below reflect a contraction.

“March and April are traditionally the busiest months for architecture firms, so we should get a clearer reading of underlying momentum over the next couple of months,” AIA chief economist Kermit Baker said in a press release. “Hopefully the relatively mild weather conditions recently in most parts of the country will help design and construction activity move ahead at a somewhat faster pace.”

Project inquiries nationwide were 59.5 in February compared to 55.3 in January, while design contracts increased slightly from 50.9 in January to 51.7 in February.

In the index’s regional breakdown—which is measured as a three-month average—the South came in at 51.1 for the period while the West, Northeast, and Midwest reported contractions in billings with marks of 49.9, 49.5, and 49.3, respectively.

Multifamily residential came out ahead in the index’s project sector breakdown—which is also calculated as a three-month average—at 53.0, followed by commercial/industrial at 52.3. The institutional and mixed practice sectors reported contractions at 48.1 and 47.7, respectively.