The Daily Digit is the story behind the numbers that make our world turn. Today we’re looking at the only thing more annoying than telemarketers: robocalls. Last year, the Federal Trade Commission received a record 4.5 million complaints about unwanted robocalls, the number having steadily increased from 2.2 million complaints in 2013. While there are some legitimate uses for robocalls — such as doctors’ offices confirming appointments and schools alerting parents of closures — they are often linked to criminal scams aimed at getting unwitting consumers to hand over their personal information. Even though the FTC introduced the National Do Not Call Registry in 2004 to help curtail the problem, the rising number of complaints speaks for itself. While other solutions are being worked out, it’s best to just ignore suspicious robocalls.