Architects have long watched the rise and fall of the AIA's Architecture Billing Index, but interior designers haven't had such an index until last November when the American Society of Interior Designers (ASID) launched its own. In its first report, ASID notes that both billing and inquiry indexes have been at about 50 for the past four months, indicating modest industry growth. Commercial reported at 55.9; institutional at 55.4; and residential at 57.1.

"Interior designers have good reason to be optimistic," said ASID economic advisor Jack Kleinhenz in a press release. "The renewed health of the U.S. economy is becoming evident in interior design. Both billings and inquiries have shown modest improvement across the board in the first quarter. Looking forward, we can expect that level of growth to continue, with possible seasonal boosts in some sectors."

The ASID business performance index tracks performance data for billings, inquiries and product sales. Each month, ASID surveys 300 firms to gauge billings, business conditions, and economic outlook—asking the firms to report on past billings and to speculate on business for the next six months. Most of those firms provide interior design services only, but some provide architectural, engineering, and other related services. Each quarter, ASID also asks these firms to provide information on product purchase and specification activity. The results are compiled into diffusion indexes centered on 50, with scores above 50 indicating an increase in billings, and scores below 50 indicating a decline.

"The ASID index is intended to differentiate interior design performance measurements from those that are used in the construction and architecture industries," said Michael Thomas, ASID president in a press release. "In addition to a focus on interior design billings, the index monitors key indicators such as product selection. This information is a valuable resource for keeping our members apprised of the industry outlook."