One-third of all donations on the popular fundraising site GoFundMe goes towards health care costs, the company’s CEO told CBS News.

Founded in 2010, GoFundMe helps users create fundraisers for dozens of categories, including education, faith and business. Nearly 250,000 campaigns have been set up through the site to help pay for health care costs, raising $650 million in contributions, according to the company’s website.

Solomon said he never expected such a large portion of campaigns to be focused on health care.

“When we started in 2010, it wasn’t purposefully set up and built to be a substitute for medical insurance,” Solomon told CBS MoneyWatch. “We weren’t ever set up to be a health care company and we still are not. But over time, people have used GoFundMe for the most important issues they are faced with.”

Over the past few years, crowdfunding — raising small amounts of money from a large number of donors online — has become one of the main ways families seek to pay medical expenses.

One possible reason for the rising demand in crowdfunding health care costs could be the drop in health insurance coverage in recent years.

According to a new report from Gallup, uninsured rates in the U.S. have reached a four-year high, with nearly 13.7% adults in the U.S. reporting they are uninsured. Coverage is at its lowest since the Affordable Care Act’s individual health insurance mandate was put into effect in 2014, Gallup said. According to the report, about seven million more adults are without health insurance since the number started rising in 2016.

During the recent government shutdown, furloughed workers turned to GoFundMe to help pay for medical expenses, including CPT Amy Chandler who need help funding her battle with breast cancer and a Maryland grandfather seeking help for his diabetic granddaughter.

Solomon told CBS that the site has turned into a “take action button” for a number of causes.

“People want to help, and we actually solve big problems,” Solomon said. “While we didn’t set out to be one of the most influential health care companies in the world, if we have to serve that purpose, I feel very proud about that.”

Correction, Jan. 30

The original version of this story misstated the source of the information that nearly 250,000 GoFundMe campaigns have been set up through the site to help pay for health care costs, raising $650 million in contributions. That information came from GoFundMe’s website, not CEO Rob Solomon.

Write to Gina Martinez at gina.martinez@time.com.