Hmm. I wonder why I thought I'd bought eight books in February.
Looking at Calibre, my Google spreadsheet and Amazon Manage My Kindle (I don't think I bought books for myself anywhere else in February), it looks like I bought seven.
Well, that's all for the better, then.
So... seven books (out of the ten-per-month or 120-per-year I'm allowing myself) at an average cost of $2.87 - that's as high as it is due to one book over $6 and another near $5, both pre-orders in series I've been enjoying and both books I read immediately - and both would have been more expensive if not pre-ordered, as the price fluctuated quite a bit during the pre-release period and Amazon kindly locked the final price in at the lowest it was.
Also acquired five free books (three of them eARCs I'm going to have to read and review soon - all are books I would have bought otherwise), so I did fairly well in not expanding the overall pile of unread books, too.
Three pre-orders for March so far - again, the real challenge will be to keep impulse buys down, but I trust/hope I can stick to the pre-orders + possibly any good deals on those already on my wishlist.