LOUISVILLE, Ky. (WDRB) --  Kentucky saw a decline in union workers in 2017 as the state’s right-to-work law took effect, according to new federal data.

The state had 16,000 fewer workers who were members of unions in 2017 compared to a year earlier, while the share of workers who belong to unions fell to 9.6 percent, from 11.1 percent in 2016, according to the U.S. Bureau of Labor Statistics.

The share of union workers in Kentucky fell last year even while holding steady for the U.S. as a whole at 10.7 percent.

The right-to-work law, fast-tracked by the Republican-controlled legislature last January, prevents employers at organized workplaces from deducting union dues from workers’ paychecks without the employee’s consent.

But the law is being phased in over several years, so it’s unclear whether the state’s decline in union members is due to right-to-work or other factors.

“There have been a number of union shops that have moved overseas or simply closed in the past year,” said Bill Londrigan, president of the Kentucky AFL-CIO, an umbrella group for unions. He cited General Electric’s former lighting plant in Lexington, among other examples.

While unions are worried about the long-term effect of the law, not many workers have chosen to stop paying dues while still enjoying the protections afforded by labor contracts, Londrigan said.

“It may have some impact down the road, but we are not seeing a huge impact at this point from people dropping out of unions,” Londrigan said.

Timothy Gilliam, deputy Kentucky director for Americans for Prosperity, a group that favored right-to-work, said it’s “probably too early to tell” whether the decline is because of the law’s impact.

In the debate over the policy last year, some supporters of right-to-work argued that Kentucky might see more union jobs because of the law’s economic benefits.

“We never claimed that right-to-work was guaranteed to grow union memberships,” Gilliam said. “But in some right-to-work states, as the economy has grown, so has the number of jobs, which includes union jobs as well.”

The new law applies only to labor contracts that are signed or renewed after Jan. 9, 2017, when Gov. Matt Bevin signed the legislation.

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There are many workplaces that remain unaffected because their contracts predate the law.

Ford Motor Co.’s roughly 13,000 workers at its two Louisville auto plants, for example, won’t become subject to right-to-work provisions until the United Auto Workers hash out a new agreement with the company in 2019.

Londrigan said a “significant” number of labor contracts are affected by right-to-work, but he couldn’t say how many.

The percentage of the state’s workforce belonging to unions is at its lowest point since 2011. The share has been as low as 8.6 percent in 2008 and 2009, when the economic recession decimated union-heavy industries like manufacturing and construction.

While the number of Kentucky workers who are union members dropped in 2017, the number who are “represented by unions” grew by 4,000. The latter category includes union members and those whose jobs are subject to collective bargaining even if they do not belong to a union.

The total number of workers in the state grew by 100,000 to 1.81 million, according to the data, which is based on a national survey.

The share of union workers nationally has been falling for decades, particularly in private industry.

In 1983, the national union share was 20.1 percent – almost twice as high as today.

Reach reporter Chris Otts at 502-585-0822, cotts@wdrb.com, on Twitter or on Facebook. Copyright 2018 WDRB News. All rights reserved.