An index of architect billings increased by a healthy margin last month, according to the American Institute of Architects. The index, which provides an indication of future construction spending, grew to 54.7 from 50.4 in October, the strongest growth in billings since January. “Iowa architecture firms are continuing to report strong billings, inquiries and new design contracts with no large concerns with potential downturns this year,” said Jessica Reinert, AIA Iowa executive director. “Instead the challenge for the coming year seems to be the lack of qualified employees to allow firms to continue to take on larger project loads. Our career center has the most open positions listed that it has had in quite a few years.” On a regional basis, the Northeast led billings with a score of 56.8, followed by the Midwest at 53.1, the South at 50.5 and the West at 49. By sector, billings were strongest for commercial/industrial and mixed-practice projects, with both scoring 53.8. They were followed by multifamily, 51.2, and institutional, 50.8. The project inquiries index was 63.1 and design contracts registered 54.6.