My credit score seems to bounce back and forth over a 30'ish point gap. I have changed nothing (edit: that I know of).
- I have the same number of credit cards
- I've never had a late payment
- I consistently have an overall credit utilization between 1% and 18%.
In fact, in the most recent reporting on Credit Karma, my overall credit usage was 16%, yet my score dropped by 36 points.
Do they score credit cards separately? For instance, I had ~28% utilization on one card and ~3% utilization on another card.