The federal government is trying for the first time to estimate how many senior citizens nationwide are the victims of abuse, neglect or exploitation — and the numbers are staggering.

In a new report released Monday, the federal Administration for Community Living estimated that in 2016, 1.5 million cases of abuse were reported to adult protective agencies around the country, and that about half of those of those reports were deemed worthy of further investigation.

And that is probably just the tip of the iceberg.

Research indicates that only one out of 24 cases of elder abuse or neglect is ever reported to authorities. So if 1.5 million cases were reported, the total number abuse cases could be more like 20 or 30 million.

"We have a virtual public health epidemic on our hands," said Stephanie Whittier Eliason, who is leading the project to assemble the national statistics. "The number of of people who could possibly be experiencing the phenomena is huge."

The new report is the first effort to get a national elder-abuse data set, she said. "Because it is state based, there has not been the opportunity in the past to understand what elder abuse, neglect and exploitation looks like, who experiences it as well as who perpetrates abuse, neglect and exploitation, because every state has established their own unique system. So this will be the first time we'll be able to get an understanding of the phenomena across the country."

In Massachusetts, the Executive Office of Elder Affairs reported 9,800 confirmed abuse and neglect cases in the state in 2017, a nearly 40 percent increase over 2015.

Part of that growth is just better reporting; in Massachusetts and across the country, states are setting up new reporting systems to track elder abuse and to train community leaders to recognize it, so case numbers are quickly rising.

But with Americans living longer — and living longer in their own homes — the opportunities for abuse are also expanding, said Alice Bonner, the Massachusetts secretary of elder affairs.

“The fastest growing type or subtype of maltreatment or abuse is actually financial exploitation,” Bonner said. "We are seeing that scams and programs that try to take older people's money through a variety of means are increasing across the country.”

And it's not just strangers taking advantage of the elderly.

"It turns out that somewhere between 50 and 60 percent in general of perpetrators are actually family members, particularly with financial exploitation.” Bonner said.

Still, one of the biggest categories of elder abuse is self-neglect — a senior who has simply become unable to properly care for oneself and winds up injured or in financial ruin.

"Sometimes people are become less able to take care of themselves in the community, and sometimes no one realizes it, and so they are not eating well," Bonner said. In other cases, "people who are unable to manage finances, they stopped paying their bills, they don't pay their rent and all of a sudden they're evicted and they become homeless. These cases are growing, and it is real."

Bonner said her agency is working with communities to help identify seniors who could be at risk of abuse or exploitation.

And the state has been steadily increasing its elder protection budget, from $23 million in 2015 to $29 million this year.

If you have any concern that a senior citizen may be in danger, Massachusetts has a central hotline at 800-922-2275