Sales Stats

Mathematics has always been my week point. I don't enjoy working with numbers but sometimes there is a need and a benefit.
Last evening I impressed my DH some what (he's very mathematically orientated)by working out, all by myself, how often I make a sale in my Etsy shop. I aways write on my one page planner calendar when I get a sale and so I started by counting the day after that sale as day one and then stopped counting when I came to the next sale. I had seventeen sales to work with and so I totalled up the days between the sales and divided them by the number of sales, seventeen, and arrived at the fact that I have a sale once every 6.76 days. Going by that, my DH said to me last evening,that I was due a sale in the next day or three and guess what? I got a sale overnight!
When I told my DH this morning he said,'Well done. I'm so impressed with you monitoring your sales like that'.
Now, to some folk this is very basic mathematics and you won't be interested at all but for others who are like me, I hope it helps you to work out when you may just be expecting that next sale. It won't happen mind, if you don't maintain your shop, promote your shop and look after the customers you have.