Thanks SO MUCH

Providing service, my job involves a lot of saying "thanks." I found myself saying "Thanks so much" quite a bit. Too often. How did "so much" get involved?

Now that I'm aware of it, I've been able to suppress it some. But now I notice it all the time when other people say it. Is this something that just popped up more within the last year?

Well, enough babble. Thanks so much.