Counties that voted for President Barack Obama in 2008 and 2012 but flipped to President Donald Trump in 2016 still lag behind the rest of the country in several key economic indicators, a new study found.

Researchers examined economic outcomes in the 204 counties with available data among the total 207 counties that Obama won in both his presidential runs but Trump carried in 2016.

Most of these counties are concentrated in the upper Midwest.

The study found that flipped counties currently experience slower growth both in employment rates and in rates of new businesses creation compared to safe Democratic or Republican counties.

The gap has only grown since 2016.

Flipped counties also experienced disproportionate levels of population loss compared to the rest of the country.

Trump campaigned heavily on economic issues in those areas in 2016, making ambitious promises to bring back manufacturing and other jobs that were lost to offshoring or automation.

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Counties that voted for President Barack Obama in 2008 and 2012 but flipped to President Donald Trump in 2016 still lag behind the rest of the country in several key economic indicators, according to a new study from the Economic Innovation Group.

The study examined economic outcomes in the 204 counties with available data among the total 207 counties that Obama won in both his presidential runs but Trump carried in 2016. Most of those counties are concentrated in the upper Midwest states of Wisconsin, Iowa, Michigan, and Minnesota, with more clusters of such counties located in upstate New York and Maine.

Read more: Trump warns of a 'market crash the likes of which has not been seen before' if he loses 2020 election — but economists are worried he's causing a recession on his own

The researchers found that in general, those counties fared poorly in terms of economic growth prior to the 2016 election, and "were more likely than consistently Democratic or Republican counties to have suffered a severe downturn during the Great Recession and to have experienced a sluggish recovery afterward."

In all, those trends have continued through the Trump administration. Analyzing data from the Bureau of Labor Statistics and the US Census Population Estimates, the EIG study found that:

Flipped counties currently experience slower growth both in employment rates and in rates of new businesses creation compared to safe Democratic or Republican counties.

The gap in employment rates between flipped counties and non-flipped counties has only widened since the 2016 election.

Flipped counties have also experienced disproportionate levels of population loss compared to the rest of the country, with 53% losing some of their population since 2016 and 94% losing people of "prime working age" in the last 10 years, compared to Republican areas losing 53% of working-age people and Democratic areas losing 35% in the same time-frame.

While rates of economic growth are largely converging and occurring at similar rates in safe Republican areas and safe Democratic ones, flipped counties lag behind those areas in terms of both employment growth and the creation of new businesses.

Traditionally Democratic and Republican areas have experienced year-over-year employment growth at rates between 1.5% and 2% by December 2018, while flipped counties saw employment rate growth of just 0.66%.

Similarly, those same Democratic and Republican continues both saw approximately 2% growth in rates of new business creation in December 2018, while flipped counties saw between 0.5% and 1% growth at that same time.

While the EIG report noted that while "places don't change overnight, and any president has limited power to reorganize local economies," Trump heavily campaigned on economic issues, making ambitious promises to bring back manufacturing and other jobs that were lost to offshoring or automation.

These new economic data are particularly noteworthy given the significant role those "flipped" counties played in deciding the 2016 election, and the importance they will hold in deciding the 2020 election as well.

Read more: Trump's approval rating is underwater in 8 major 2020 battleground states, and it's a troubling sign for his reelection prospects

Morning Consult, which conducts daily surveys of more than 5,000 registered voters to track Trump's approval rating, recently found that Trump had a net-zero or negative approval rating in nine critical swing states that, except for New Hampshire, he carried in 2016.

Many of those states hold large concentrations of flipped counties, with the survey finding that he holds a net approval rating of -13 in Wisconsin, net -12 approval in Michigan and Iowa, and net -4 approval in Ohio.

And according to a Quinnipiac University poll conducted from June 6-10, 70% of Americans described the current state of the economy as "good" or "excellent," but just 41% said Trump deserved credit for the state of the economy.

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