Y = [W + (D-d)]TQ / M x NA, where W is weather, D debt, d monthly salary, T time since Christmas, Q time since failed quit attempt, M low motivational levels and NA the need to take action.
Minimum Y is supposedly on Jan 24th.
And Y is???
Apparently, up to 30% of the UK population suffers from SAD, but it's extremely rare to find anyone with SAD within 30 degrees of the equator. See you in Spring, suckers!