The Zions Bank Small Business Index for Utah continued to decrease in May, the third consecutive month of declines because of weak housing and unemployment.

The index for May was 89.3, down from a revised 91.2 in April. The baseline for the index is 100, a number economists gave the index in 1997, when the index was created.

The index was developed by Jeff Thredgold of Thredgold Economic Associates, the economic consultant to Zions Bank, and considers 14 factors, such as unemployment, job growth, bankruptcies, the Gross Domestic Product growth and interest rates, said Kendall Oliphant, senior vice president at Thredgold Economic Associates. The index is a proprietary model and not all the factors are revealed.

Utah's unemployment rate was estimated at 3.1 percent in April, down from 3.3 percent in March. Total Utah employment is up an estimated 24,800 jobs during the past 12 months.

New home construction is down, which also affects small business owners. In Utah, homes are built by large companies, but small businesses provide services as architects, engineers, suppliers, furnishers and landscapers. Many of these firms have struggled, according to a report accompanying the index.

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