The number of small business that aren't able to find enough workers has matched the highest level ever recorded.

The percentage of small companies not able to fill open positions hit 36 percent in June, according to the NFIB Research Center, matching the survey's record high set in November 2000. (The data goes back to 1973.)

“Labor markets are very tight, for both skilled and unskilled workers,” wrote William Dunkelberg and Holly Wade, chief economist and director of research at NFIB, respectively. “More firms are looking for workers than workers looking for a job. And the hiring strength is in industries that pay well: construction, manufacturing, and financial services.”

Source: "NFIB Small Business Economic Trends," July 2018. NFIB Research Center.

The difficulty in finding qualified workers comes at a time when small business optimism is booming with the survey's main index posting its sixth highest reading ever. For the month of June, the index came in at 107.2, down 0.6 from May. Since December 2016, the index has averaged an "unprecedented" 105.4, well above the 45-year average of 98 and rivaling the all-time high of 108 in July 1983, the researchers said.

The findings represent yet another indication that the U.S. labor market is either at or beyond full employment following Friday’s Department of Labor report on the employment situation. The monthly publication showed that the economy added 213,000 jobs last month, well ahead of expectations and maintaining the trend of hot job creation.

The unemployment rate – which measures the number of people without a job but seeking work against the total number of people in the labor force – ticked upward to 4 percent as the competitive labor market attracted people off the sidelines.

“Small business owners continue to report astounding optimism as they celebrate strong sales, the creation of jobs, and more profits,” said NFIB chief executive Juanita Duggan. “The first six months of the year have been very good to small business thanks to tax cuts, regulatory reform, and policies that help them grow.”

The organization found in their most recent report that 21 percent of small business owners cited trouble finding qualified workers as the single most important business problem.

According to July's Job Opening and Labor Turnover Survey (JOLTS) published Tuesday, there were 6.6 million open positions in May, more than the 6.1 million unemployed persons in during the month, according to the Bureau of Labor Statistics.

Under normal circumstances, the mismatch would be galvanizing higher wages. However, average hourly earnings rose just 2.7 percent annualized in June, up two-tenths of a point from May.