Hawaii’s unemployment rate held at 2.8% in May for the third straight month, but the number of people in the labor force fell to the lowest level in more than four years as the state’s economy continued to lose momentum.

It was less than two years ago that the state’s unemployment rate was at an all-time low of 2.2% in October and November 2017. But that number has been rising amid a slow-growth environment. Tourism, the state’s No. 1 industry, continues to see declining visitor spending; auto sales are declining; bankruptcies are rising; and the labor market is shrinking.

“It seems we are losing more workforce, both in the self-employed and payroll employment,” said Eugene Tian, chief economist for the state Department of Business, Economic Development and Tourism. “Consistent with the decline in the visitor spending, all tourism related- industries lost jobs in May. Labor market indicators are mixed in May, but the general trend is that our economy continues slowing growth.”

The number of people in Hawaii’s labor force, which includes those who are employed, those who are unemployed but actively seeking work and those who are self-employed, fell to 667,800 in May from 670,450 in the previous month, according to data released Thursday by the state Department of Labor and Industrial Relations. It was the lowest number in the labor force since there were 668,290 in October 2014.

The number of people employed in May fell to 648,850 from 651,450 in the previous month. That was the lowest since 649,261 in June 2015.

Those unemployed fell to 18,900 from 19,000.

Labor force data is compiled from a telephone survey of households.

“If the labor force decreases, there are two reasons,” Tian said. “Either people give up and are not looking for jobs, or they’re not employed. That is one group. The second group is they move to the mainland. The mainland economy is better than ours, and maybe they’re looking for a better opportunity.”

Nonfarm payroll jobs, which are calculated from a mail survey of employers, rose by 1,200 in May from the previous month. The largest gain was an increase of 400 jobs in education and health services. The trade, transportation and utilities category had the largest loss of jobs at 600, followed by leisure and hospitality at 500.

The unemployment rate fell in all four of the state’s major counties. State and national labor force data is adjusted for seasonal factors, but the county jobs data is not seasonally adjusted and thus does not take into account variations such as the winter holiday and summer vacation seasons.

Honolulu County’s rate fell to 2.5% from 2.6%, Hawaii County’s rate dropped to 3.3% from 3.8%, Kauai County’s rate decreased to 2.5% from 2.9% and Maui County’s rate dipped to 2.5% from 2.8%. Within Maui County, Maui’s rate declined to 2.5% from 2.8%, and Lanai’s rate fell to 0.9% from 1.3% while Molokai’s rate rose to 5.4% from 4.7%.