The Architecture Billings Index, a measurement of demand for non-residential design services, rose in December -- the tenth month of growth in the U.S. last year.
One of many national economic indicators related to development, the index provides a glimpse 9 to 12 months before construction spending is reported.
December's ABI score was 52.2, up from November's 50.9. The index uses 50 as flat activity and anything above that is viewed as an increase in demand.
As for broader economic implications, AIA's chief economist Kermit Baker says the last stalwart resisting the post-recession construction boom has been public buildings.
"Particularly encouraging is the continued solid upturn in design activity at institutional firms, since public sector facilities were the last nonresidential building project type to recover from the downturn," Baker said in a statement.
The U.S. as a whole saw more months of growth than contraction in 2014, with architectural billings dipping only two months out of 12.
The regional averages provide a more honed narrative. The strongest December growth was concentrated in the South, 56.8, and West, 52.9. Meanwhile, the Midwest hovered slightly above neutral with a score of 50.8, and the Northeast pulled down the national average at a decrease in demand of 45.5.