A new month and a new spam number to my phone. CID: Out of Area. Number: 408-879-0227. I don't want these spammers to know my number gets a live voice; so, I never answer AND I never let it go to voice mail (because it's off). Number is being blocked. I don't get too many repeat calls when I pick up the number on the first ring and immediately hang up. Try it out, you may receive fewer repeat calls from the same number.
Answered (because I'm in the 408 area code, so I *might* know someone with that number), but nobody there, and hung up after several seconds. Number is "flagged" on CallerDB.com with notation "Ignore calls from this number."