Drivers whose rating slid three weeks in a row

Driver quality managers want an early warning: a driver whose weekly average rating fell for three consecutive weeks, meaning week W is lower than W-1, W-1 is lower than W-2 and W-2 is lower than W-3 (so four consecutive weeks are involved). Weeks run Monday to Sunday and the week is identified by its Monday date (YYYY-MM-DD). Only trips with a rating count, and the weekly average is the plain average of the ratings given that week. Every driver has rated trips in every week of the data they appear in, so consecutive rows of the weekly table are consecutive calendar weeks; still, require the four weeks to span exactly 21 days.

Task: return driver (name), first_alert_week (the earliest week W that completes such a slide) and alert_weeks (how many weeks W qualify for that driver). Sort by alert_weeks from high to low, then driver A to Z.