Different credit reporting bodies use different formulas to calculate credit scores. However, they use the same type of information – credit history and demographic profile.
So they’re going to look at how many credit applications you’ve made, who they were with, what they were for, how much they were for and your repayment record. They’ll also look at your age and postcode. They’ll also look to see if you’ve had any bankruptcies or other relevant legal judgements against you.
Your score can change if your demographic profile changes or new information is added to your file (such as a new loan application) or existing information is removed from your file (because it has reached its expiry date).