The long-lasting impact of the 2008 financial crisis and lingering tight job market is showing up in the country’s growing income gap.

The income gap among Americans has widened by 10% nationwide over the past 20 years, according to new survey released Monday by Bankrate.com (RATE). Despite this growing trend, a second report shows that one in five Americans will become rich for parts of their lives, meaning they make at least $100,000 a year, according to the Associated Press.

Bankrate reports the income gap in America is growing fastest among those ages 35-to-44 at a rate of 21% from 1992 to 2012. This is higher than any other age group and more than double the average increase for all age groups, at 10%. Those in this age group are at their prime years for solidifying future wealth, the survey reports, which can be worrisome to long-term income growth prospects.

Chris Kahn, Bankrate research and statistics analyst,says the two major factors contributing to the widening income gap are women increasingly becoming the household breadwinner and a growing immigrant population.

“The economy today is different than it was 20 years ago,” Kahn says. “Demographically, immigrants are coming into this country every year and they earn less. Also, there are a greater percentage of women who are the main breadwinners in their home—and they earn less dough on average than men.”

Employers have also sent millions of jobs overseas, Kahn says, specifically in the manufacturing and service sectors.  “Many people have had to compensate by taking lower-paying jobs,” he says.

AP reported Monday that 20% of U.S. adults will become rich at some part of their lives, which could make it harder to reduce the country’s wage inequity.

The AP reports that this new class is made up largely of older professionals, working married couples and more educated single people. They will have an income of at least $250,000 or more at some point during their working lives, which places them temporarily at the top 2% of earners. Members of this group typically earn about $100,000 or more annually, placing them in the top 20% of earners in the country.

But as far as the ‘new rich’ are concerned, Kahn says many wealthy people are not making this cash off of traditional incomes like high-paying jobs. Instead, they have gotten tax breaks in the form of capital gains and are bringing in investment incomes.

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