The goal of one-ring phone scams isn't to get people to answer, but to get them to call back.

Youmail, a cellphone blocking app, says around 60 billion robocalls have been placed to U.S. numbers this past year. The company says almost 50% of those calls are scams.

One-ring scams only call to make the phone ring once. It's the type of spam call that does the most damage if the number is called back.

Ulster County District Attorney Holley Carnright has been warning New Yorkers about one-ring scams that use the similar area code technique.

"You risk being connected to a phone number outside the U.S., you may wind up being charged a fee for connecting, along with significant per-minute fees for as long as they keep you on the phone. These charges may show up on your bill as premium services, international calling, or toll-calling," said Carnright.

Ulster County urges anyone who receives a one-ring call to reach out to their Division of Consumer Affairs.