Your single-biggest credit score increase – What did you do?

I’m looking for credit card users who have ever experienced a large credit score increase (in a short period of time) to tell me what they did or what changed that caused the improvement. Did a missed payment finally fall off your credit report? Did you pay down a large card balance? Did you add some different types of trade lines to help balance out your mix of credit? Requirements: Please include what your credit score was before and what is was after the big jump. A big jump can be as low as 20 points, but
I’d prefer increases of 40 points or more.