Conversion Rate by Channel

For each acquisition channel return the percentage of visitors who converted, rounded to two decimals. Order by channel.

Table schema

Visits(user_id INT, channel VARCHAR(10), converted INT)

Sample data

user_id | channel | converted
1 | email | 1
2 | email | 0
3 | ads | 0
4 | ads | 0
5 | ads | 1