Most of them were probably made by people in India being paid a token amount (who may not have even realised that they weren't working legitimately for the IRS). Those 61 probably represent the ones that actually made the money.
Actually, they understood that, perfectly. Your good scammers need to be intelligent to actually convince people to part with their money, and they need to know that they are running a scam, not actually representing a governmental agency in another country.
After receiving 4 calls in one day from them, I started calling them back. They would ask for my name, and I would remind them that they called my number, and left messages insisting that I owed money to the IRS, so all they needed to do was look at my phone number, and tell me who I was and how much I owed. They would then hang up on me. After about a dozen attempts, they recognized my number, and once answered the phone with a "f*ck you" and immediately hung up. After the 20th time I called them back, in a row (yes, I was bored, and apparently there were 3 or 4 people answering calls on the number they were using at the time, so I started recognizing their voices,) I lied to them and told them that I had just called the IRS, who denied having anything to do with this, and who had directed me to the FBI, who would be calling them, shortly. In a rare moment of "fsck this" the scammer said "Yes sir, you are right, this is a scam. If you fell for it, we were going to get you to send us all of the money in your bank account." I was shocked by this, and also excited, because I was recording the call (I'm in Virginia, a 1 party consent state.) So I drew him out, and he explained to me that he wasn't worried about the law coming to get him, because "we have been doing this for years. They never catch us. They never going to catch us." He then asked me, politely, if I would please stop calling them. I told him to stop calling my number, if he didn't want to keep hearing from me, dozens of times for every call they made to me, and he agreed.
They did call me back the next day (darned scammers, not keeping a good Do Not Call List,) but, after that, it was over a month before they put me back into the regular rotation.
Yes, I still have the recording. I had plans to post it on youtube to shame the government into some kind of action, but, when I looked it up online, I found that this was so well known for so many years that it was clear that the scammer was essentially right... no one was coming for them.
This news article made me smile. I kind of hoped they got the "they never going to catch us" guy.