Who knows. I live in the City and being a pet sitter I get a lot of out of state callers bc it's a college town with a tons of  rich transients and transplants. People travel a lot and need pet sitters.  That said, everyone hangs up now, even my own friends , doctor's , family , neighbors:  first of all they can't figure out how to bypass voicemail no matter how many times I've instructed (bc no one listens to anything). Also, No one leaves a message bc everyone is conditioned to the instantaneous 4 word response of texting or the often immediate answering of cell phones, facebook posting, twitter nonsense, the complete and absurd immediacy of everything has even made voice mail a thing of the past.  I don't know anyone who has a landline, most aren't even using  the cell to make phone calls & if they do, they won't leave message bc it takes too long to listen to the person's outgoing message (20 seconds).  Calls which come in could be from a legit caller, or not. I'll never know.