– Do divorce rates grow exponentially with age? A new survey shows that the divorce rate has doubled for Americans over age 50, and tripled among Americans over 65.

“At a time when divorce is becoming less common for younger adults, so-called ‘gray divorce’ is on the rise,” the Pew Research Center said.

In 2015, the divorce rate among married persons over 50 was 10 in 1,000, an increase from 5 in 1,000 in 1990. Among those 65 and older, the divorce rate has tripled to 6 per 1,000.

Pew said the divorced rate among those 50 and older is partly linked to the aging of the Baby Boomer generation, the age cohort 51-69 in 2015.

As young adults, this generation had unprecedented levels of divorce. Remarriages tend to be less stable than first marriages, with the divorced-and-remarried having twice the divorce rate as those married once. Among the divorces of adults age 50 and older, 48 percent were in a second or later marriage.

The risk of divorce is also higher among those who have been married for a shorter time.

At the same time, Pew said a “significant share” of divorces are among those 50 and older. About 34 percent of those divorcing after 50 years old had been married for at least 30 years, and 12 percent were married for over 40 years. Many of these divorcees cited dissatisfaction in their marriages and a desire to seek opportunities to pursue their own interest and independence late in life.

These older divorcees, especially women, face more financial insecurity than married and widowed adults.

As for younger age cohorts, the divorce rate slightly increased among married adults age 40-49.

Divorce rates have dropped 21 percent among those aged 25-39, from 30 in 1,000 to 24 in 1,000 from 1990 to 2015. According to Pew, this decline is in part attributed to younger generations’ delay in marrying. It is also attributed to the phenomenon of the college-educated being more likely to marry and also being less likely to divorce.