Write a SQL query to calculate the month-over-month growth rate of qualified leads generated by paid acquisition channels at Capchase.
Use the provided leads and acquisition_channels tables. Treat each month with at least one qualified lead from a paid channel as a reporting month. The first reporting month should have a NULL growth rate.
month, qualified_leads, and growth_rate_pctgrowth_rate_pct should be rounded to two decimal places and ordered chronologically| Column | Type | Description |
|---|---|---|
| lead_idPK | INT | Unique lead identifier |
| generated_at | TIMESTAMP | Timestamp when the lead was generated |
| channel_id | INT | Acquisition channel identifier |
| lead_status | VARCHAR(30) | Qualification status of the lead |
| Column | Type | Description |
|---|---|---|
| channel_idPK | INT | Unique acquisition channel identifier |
| channel_name | VARCHAR(100) | Name of the acquisition channel |
| acquisition_type | VARCHAR(30) | Broad channel classification |
| is_paid | BOOLEAN | Whether the channel is paid acquisition |