In this exercise you need to calculate D14 retention rate for users who signed up on Feb 1, 2018.
The purpose of this exercise is to finish the retention curve query we started in the previous lesson. It gives us the number of active users per day. The challenge is to complete the query and calculate retention rate for each day.
Submit only the integer part of the retention rate as the answer. For example, if D14 retention rate is 17.666% submit 17 as the answer.