All authors can track their sales immediately by watching rankings on Amazon. As far as I know, no other huge on-line retailer does this. It becomes as obsession if you're not careful.
Amazon recently added AUTHOR rankings. That is, the total of the books sold by a given author provides a ranking within the zillion or so authors whose books sell on Amazon. When Amazon told me about this, I chuckled and went to take a peek at my own author ranking. Knowing there are a zillion authors, I expected to be in at least the six-digit area (the higher, the worse on rankings). Much to my amazement, I was actually in the five-digit world. Well, that's something to write home about, so here's my proof that I'm way up in the world of Amazon authors FOR THE HOUR since rankings change hourly. Still, one captures these highs so they can brag about them. Here's my bragging rights. That 33,931. Yay me!
My publisher also tossed a kudo my way for being in the top ranks of juvie book sales at Omnilit. Also a nice brag, so here's the snapshot I can treasure into my old age. Those three books in the middle of the top row are all mine. Not only best selling, but highest rated!