How do you calculate the rate of customer turnover?

Calculating the rate of customer turnover, or customer churn, is a very easy process. First, find the number of customers you had at the beginning of whichever time period you are wanting to calculate. Second, find the number of customers you currently have. Subtract the number of customers you had by the number of customers you currently have. Once you get this number, divide it by the number of customers you had. This will give you a percentage of how much customer turnover you have.