Write a SQL query to find the monthly retention rate of customers acquired through a specific marketing campaign at Cox Enterprises. Use the campaign named Cox Connect Spring and count a customer as retained in a month when they have at least one activity on or after their acquisition date. Include the acquisition month and later months represented by campaign activity.
activity_month, retained_customers, cohort_customers, and retention_rate.retention_rate is a percentage rounded to two decimal places.| Column | Type | Description |
|---|---|---|
| campaign_idPK | INT | Unique marketing campaign identifier |
| campaign_name | VARCHAR(100) | Campaign name |
| channel | VARCHAR(50) | Primary marketing channel |
| Column | Type | Description |
|---|---|---|
| customer_idPK | INT | Unique customer identifier |
| campaign_id | INT | Campaign credited with customer acquisition |
| acquired_at | DATE | Customer acquisition date |
| customer_segment | VARCHAR(40) | Customer marketing segment |
| Column | Type | Description |
|---|---|---|
| activity_idPK | INT | Unique activity event identifier |
| customer_id | INT | Customer associated with the activity |
| activity_date | DATE | Date of customer activity |
| activity_type | VARCHAR(40) | Type of customer activity |