Christian Hartmann/REUTERS

America's community colleges may need to start teaching courses for women on "How to Be Old," because America's ladies are not doing a great job of figuring it out on our own.

Extreme poverty among women over age 65 who lived alone jumped between 2011 and 2012, according to a new report from the National Women's Law Center, "Insecure & Unequal," analyzing recently released Census data.

"It's really something that was unexpected," said Katherine Gallagher Robbins, a senior policy analyst at the National Women's Law Center. After being fairly stable for the last decade, the percent of women over 65 subsisting on shockingly low annual incomes—less than $5,500 each year—edged up from 2.6 to 3.1 percent. "That's a big jump," she said, an 18 percent increase in just one year.

Overall, 18.9 percent of women over 65 who lived alone were below the federal poverty threshold of $11,011 for single individuals. That's a high share of a rapidly growing group: The number of working people working over 65 is up 67 percent in the last decade.

Gallagher Robbins didn't have an explanation for why the rate of extreme poverty jumped, but suggested one thing her group was considering was that reductions in Social Security Administration funding might have made it harder for individuals eligible for and dependent on SSI funding to get it. But, she was quick to add, that was "pure hypothesizing."