The Architecture Billings Index, which gives contractors an idea of nonresidential construction work nine months to a year later, continued its 20th consecutive month of declining billings in September, the American Institute of Architects and software firm Deltek announced Oct. 23.

The ABI remained at 45.7, the same score as in August. An ABI of 50 represents no change in billings from the previous month, while a score above would indicate an increase and a score below 50 shows a decline. AIA bases the ABI on monthly surveys of its member firms.