Associated Builders and Contractors Inc.’s Construction Backlog Indicator (CBI) fell 16.3 percent during the past year and currently stands at 5.5 months, the lowest point reported in the 15 months that the organization gathered the data.

CBI is a forward-looking indicator that measures the amount of construction work under contract to be completed in the future. Between November 2009 and January 2010, it declined 9 percent.

“The fact that the CBI is now at its lowest point since ABC began measuring the statistic in November 2008 indicates that the nation’s nonresidential construction industry remains mired in its own recession,” said Anirban Basu, chief economist for Associated Builders and Contractors.

Given the slow recovery of the broader economy over the past three quarters, and the positive impact of the federal stimulus package, Basu said the hope had been that some signs of backlog stability would be apparent by now.

“However, all indications continue to point toward an ongoing decline in the commercial and industrial construction industry,” he said, noting that nonresidential construction tends to lag the overall economy by 12 to 24 months.

Between January 2009 and January 2010, the average backlog was down in each of the geographic regions, except the middle states, which includes the Midwest. Declines were especially sharp in the Northeast and the South, which have both experienced dips of about half a month of backlog during the past two months. The sharpest regional decline occurred in the South, falling from 8.12 months in January 2009 to 6.03 months on a year-over-year basis. The average backlog fell in all three industry segments: Commercial and institutional, industrial and infrastructure.

“While most regions experienced a decline in average backlog during the latest two-month period, with the exception of the middle states, the pace of decline was quite modest,” Basu said. “Overall, the data are consistent with the notion that while the pace of decline continues to slow, the downward trend is evident in virtually every region of the nation.”

Firms with annual revenues in excess of $100 million reported the lengthiest backlog, and the average backlog in both the $50 million to $75 million and the $75 million to $100 million categories is at its lowest level, Basu said. He noted that no firm in the $75 million to $100 million category reported an average backlog of more than five months.

“Many of these firms appear to be general contractors that continue to be underbid by larger firms with greater resources and greater capacity to undertake projects with little or no profit margin built into their bids,” Busu said. “Larger firms also may be more likely to maintain productive banking relationships, allowing them to more nimbly access available contractual opportunities.”

At 5.3 months, backlog in the commercial and institutional category is at its lowest level in the survey’s history.