Small business owners remain fairly pessimistic about how business will fare in the coming months, according to a recent survey.

The National Federation of Independent Business says its May index of owners' optimism was little changed, inching down to 94.4 from 94.5 in April. The NFIB, which lobbies on behalf of small business, compiled the index from a survey of its members. It stands at the same level as in February 2011.

One positive component of the index is a 1 percentage point increase in the number of owners planning to hire. But more than a third of those surveyed reported difficulty finding qualified workers for their openings. Three-quarters of the owners hadn't made any changes in their staffing levels in recent months.

Owners remained uncertain about the future. NFIB Chief Economist William Dunkelberg said the number of owners expecting their sales to rise in the coming months fell 4 percentage points — the third straight monthly decline in expectations for sales. The number of owners who plan capital outlays, or spending on investment or to expand, fell 1 percentage point.

"There was little improvement in the numbers to suggest that job creation would pick up a lot of steam anytime soon," Dunkelberg said.

The NFIB questioned 681 randomly selected members for its survey. The group's membership includes 350,000 small business owners.