How to estimate loss of customers due to customer support inefficiency? I have a data about customers and their activity on a website for a two-year period. Also, I have a customer support work evaluation data for a shorter period of that two-year period. The question is:

How to find out if inefficient customer support affected loyalty of customers and, in particular, how many customers were lost due to this factor?

So far, I just made a simple comparison on how many customers kept using the website after leaving the negative (unsatisfactory) or positive (satisfactory) evaluation of the customer support work. The comparison shows that the customer retention rate for customers who left negative feedback is lower than for those who provided positive (satisfactory) feedback.

I'm not an economist, but I'm sure there's a more scientific way to estimate the influence of one factor on another using statistical analysis.
The best way would be to use a regression analysis, What i would do as an economic major would be use two independent variables such as in your case level of customer support, customer feedback to see if the dependent variable "customer retention rate". also you need to use parameters for customer support evaluation, customer feed back and customer retention rate for the years. Then run a regression analysis to find if the independent variable are co-related to your dependent variable, thus you can arrive at a statistical justification for your problem.