The AIA's monthly Architecture Billings Index (ABI) came in at a score of 54.2 in August, marking the 11th consecutive month of gains. The ABI is a leading economic indicator of construction activity in the U.S., and reflects a nine- to 12-month lead time between architecture billings and construction spending nationally, regionally, and by project type. A score above 50, as seen in August, represents an increase in billings from the previous month, while a score below 50 represents a contraction.

August's score is 3.5 points higher than July's reading of 50.7, indicating that business continues to trend upward despite labor shortages and cost inflation of building materials.

“Billings at architecture firms in the South continue to lead the healthy increase in design activity that we’ve seen across the profession in recent months,” said AIA chief economist Kermit Baker, Hon. AIA, in a press release. “Nationally, growth across all building sectors remains solidly positive.”

In August, design contracts posted a score of 49.6—a 4.2-point decrease from July's score of 53.8. This was the first time since October 2016 that the number of signed design contracts dropped below the 50-point threshold.

The scores for regional billings—which, unlike the national score, are calculated as a three-month moving average—increased in three regions last month. The billings score for the West rose 4.6 points to a score of 54.2. Demand for design services in the Midwest increased by 3.2 points to a score of 52.5. Billings increased in the South, growing 1.8 points, to a score of 57. Demand for design services fell by 1.1 points to a score of 46.9 in the Northeast.

In August, the four individual industry sectors came in at higher scores compare to July, with all reporting scores above 50. The multifamily residential score increased by 1.0 point to a score of 55.6. The institutional sector grew 1.2 points to 52.3. The commercial/industrial sector's score increased by 3.5 points to a score of 53.6. And the mixed-use sector posted a score of 51.7, a 3.5-point increase from July's score of 48.2. (Results of sectors are also calculated as a three-month moving average.)