These days, the rankings for your 'Zon books don't really matter that much. There's something like 10,000,000 titles you're more or less competing against, and all it takes to get back in the top 100,000 is to run a flash sale, or promo. Add in a little advertising and it can stay there for a while. But don't spend too much on advertising because it will cut into your profits. Remember, when it comes to making decent royalties, more books means more money.
Amazon Rankings
Amazon Rankings
Amazon Rankings
These days, the rankings for your 'Zon books don't really matter that much. There's something like 10,000,000 titles you're more or less competing against, and all it takes to get back in the top 100,000 is to run a flash sale, or promo. Add in a little advertising and it can stay there for a while. But don't spend too much on advertising because it will cut into your profits. Remember, when it comes to making decent royalties, more books means more money.