Write a query that calculates the running total of sign-ups per day for the current month.
Assume sign-up timestamps are stored in signup_events. Include dates from the first day of the current month through today, excluding future dates and records without a timestamp.
signup_date, signup_count, and running_totalsignup_date ascending| Column | Type | Description |
|---|---|---|
| signup_idPK | INT | Unique identifier for the sign-up event |
| VARCHAR(255) | Email address submitted during sign-up | |
| signup_at | TIMESTAMP | Timestamp when the sign-up occurred |