The majority, if not all, research on spam calls to date has
focused either on primarily or mobile phones or a combination of
mobile and landline phones. Which makes sense considering
the size of the mobile phone market.
However, as the approximately 40 million households with
landline phones will attest to, spam, scam, robo, and all other
types of unwanted callers are just as active on landline phones.
In fact, unwanted callers top the list of FCC complaints.