I have a log of customer call data, and would like to know what kind of statistical test I could use to test for statistical significance. Customers call with a unique call reason, and fit into either one customer type, young customers or elderly customers.
Call Reason Young customers Elderly Customers Bill Enquiry 5 28 Product Problem 15 20 Product Upgrade 25 12
The numbers represent the number of calls for each call reason from each customer type. I want to know how I can test if there is statistically significant difference (with 95% confidence, say) in the type of customers that call for each call reason. For example, looking at the data, it appears that many more elderly customers call with billing enquiries than young customers. How might I rigorously test this?