In fall, warm blooded animals usually slow down as they prepare to hibernate for winter. Yet, the Architecture Billings Index (ABI) demonstrates few signs of winter slumber, with increased demand for design services in almost every category. The October ABI of 53.1, the AIA reports, is down 0.6 points from September, but any score over 50 represents an increase in billings.

The ABI is the primary economic indicator of construction activity, reflecting a nine to 12 month lead time between architecture billings and construction spending.

“Allowing for the possibility of occasional and minor backsliding, we expect healthy business conditions for the design and construction industry to persist moving into next year,” AIA Chief Economist Kermit Baker said in a statement. “One area of note is that the multi-family project sector has come around the last two months after trending down for the better part of the year.”

October’s new projects inquiry index was 58.5, down from September’s 61.0. Design contracts fell by 1.5 points to 51.7.

The South lead the regional averages with a score of 56.2, up from a score of 54.5 in September. The West trailed at 54.4, followed by the Midwest (52.6), and the Northeast at at a paltry 49.2, though up 5.5 points from the previous month.

Commercial and industrial construction led the sector breakdowns at 55.1 points, up 4.2 points from September. Mixed practice jumped 2.3 points to 54.9, and multifamily residential climbed 3 points to 52.5. Institutional sector held steady at 51.4, a drop of 0.1 from last month.

The national index, new projects inquiries, and design contacts indexes are calculated monthly, while the regional and sector categories are calculated as a three month average.