Architects experienced a setback in March, according to the American Institute of Architects' (AIA) Architecture Billings Index (ABI). The decline in March wiped out the slight growth seen in January andFebruary.

The ABI score fell from 50.7 to 48.8, the lowest score since December 2013. The slip in March could be a replay of the spring dip in billings in 2013, when billings fell from 52.0 in March 2013 to 48.7 in April 2013—before showing growth for much of the rest of the year. The fall in March 2014 could also reflect the severe winter weather that seized much of the nation at the start of spring.

It may be months before we find out whether the slowdown in billings should be attributed to a prolonged winter or something else in the economy. Fortunately, the AIA has introduced a new analytic tool to gauge future growth with the industry: design contracts. The new design contracts score of 48.2 for March also shows a retreat from 51.0 in March. (Any score above 50 indicates an increase.)

The projects inquiry index score for March was 57.9, up from February's 56.8.

Here are the national and sector breakdowns.

National Highlights:
National billings: At 48.8, down from February's 50.7, the national billings score slips after back-to-back months of growth. For three of the last six months, the index has shown growth. 
Project inquiries: At 57.9, up from 56.8, this score has stayed above 50 for well over a year. 
Design contracts: The newest metric in the ABI has shown growth for four of the last six months. The March score is 48.2.

Regional Highlights:
Northeast: The March score of 46.8 is down from February's 48.3—and it marks six months of decline for the region. 
Midwest: At 46.6, down from 47.6 for February, March marks the fifth month of contraction in a row. 
South: The March score of 52.8 is dead even with February's score. The South is nearing on two years of growth. 
West: Up slightly from 50.5 in February to 50.7 in March, this month's score continues 19 consecutive months of slow but steady growth.

Sector Highlights:
Commercial/Industrial: At 49.6, down from 51.9 in February, this sector's score closely tracks the national average. 
Multi-family Residential: March's 52.1 score is down just slightly from February's 53.5. Growth for two more months will mean two solid years of growth for this sector. 
Institutional: At 49.0, down from 49.6 in February, the March score means this sector is suffering a six-month slump. 
Mixed Practice: The 47.6 score in March is up from February's 46.6, but it is nevertheless the fourth straight month of decline for this sector.