Since the beginning of the year, I've had a total of 14 calls blocked.
But I know I get about 5 - 7 spam calls a day.
The spammers use automated dialing systems that sometimes get legitimate numbers. But most of the time, they use a similar prefix to my number so it's not blocked.
At one point NomoRobo was a great feature, but now it looks like the spammers have figured out how to defeat it.
I've long since given up reporting numbers.... it just seems like an exercise in futility.