One of the great things about publishing with Amazon’s KDP, is the instantaneous reporting of sales.  I sell more books through Smashwords, which distributes to B&N, Kobo, Sony, and Apple, but sometimes the reports of sales can lag a couple of months.  I know that Smashwords reports to me as soon as they get the reports from the retailers, but it is still a long wait.  I check in regularly at my Smashwords Dashboard, especially near the end of the month.  I like to keep track of my monthly sales as much as possible.  In the meantime, I should get back to revising Blood Trade.