Payroll service provider Paychex has teamed up with the research firm IHS to produce a new Small Business Jobs Index, which shows the Mountain region of the country leading the way in employment gains among small businesses.

The index is based on aggregated data from approximately 350,000 small businesses with fewer than 50 workers across the U.S. to provide insight into national, regional, state and metropolitan-area employment activity. The data for the index comes from a subset of the Paychex client base. The Paychex | IHS Small Business Jobs Index reached a peak of 101.15 last month and showed consistent gains in small business employment since October. Year-over-year gains of 0.33 percent in March represented the largest since May 2013.

The Mountain region led in year-over-year small business employment gains and produced the second-fastest all-employer job growth in the nation in 2013, according to the U.S. Bureau of Labor Statistics.

Among the 20 largest states in terms of population, Texas, Illinois, Washington and Wisconsin led the way in the state rankings. A sharp decline in Missouri’s small business employment last month pushed it to the second-lowest rank among states, joining Virginia, New Jersey and Maryland, which have seen weak job growth since 2013.

Among the 20 largest metropolitan areas based on U.S. population, Dallas’s small business employment indicator outpaced other large metro areas, consistent with its robust job growth overall. Houston ranked fourth, joining Riverside, Calif., and San Francisco among the top-performing metro areas.

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