A 5% drop to 45.8 for May’s Architecture Billings Index from a month earlier ended a string of positive scores (anything at 50 or above represents an increase in billings) during the first quarter. However, the new-projects index remains positive, with a score of 54.0 in May vs. April’s 54.4.

The overall drop represents continued economic uncertainty, particularly the weak job growth in recent months, said Kermit Baker, chief economist of the American Institute of Architects and author of the report. “This should be an alarm bell going off for the design and construction industry,” he said.

The commercial/industrial sector was the only one reporting an increase in design activity with a ranking of 50.7. The multifamily and residential category came in at 48.9, institutional at 45.6, and mixed-practice at 41.5.