A recent survey done by Harris Poll on behalf of Truecaller, a company that provides phone security services concludes that during the last twelve months approximately 22.1 million Americans were victims of various phone scams both on their landlines and smartphones with an average loss of $430 per victim which is a 56% increase from a similar survey done in 2015.
Phone scams come in a variety of forms including phony charity solicitations and fake IRS calls, but they all have one thing in common. They can easily steal your money if you are not careful.
The survey also showed who was being scammed and the results were interesting.  American men were almost twice as likely to become a victim of phone fraud as American women and millennial males were the most vulnerable group of all.
The survey also pointed out vulnerabilities of people on their smartphones where 72% of the fraudulent losses occurred.  In 2014, smartphones accounted for just 29% of fraudulent phone call losses.  Of course, with increased use of text messaging, fraudulent text messages open up a new venue for scammers.
TIPS
The first defense against phone scammers is skepticism.  You can never be sure when you receive a phone call or a text message as to who is really contacting you.  Even if you have Caller ID, scammers can use a technique called spoofing to make the call appear to be originating from a legitimate source.  Never provide personal information including credit card information to anyone who calls you or text messages you without confirming the legitimacy of the call or text message.  You also may wish to use services like nomorobo which screens robocalls or Truecaller which screens your phone calls and text messages.