What is the difference between the money you need from the Bank of Canada and the money you need overall for credit card payments? If you tell me that 70% of people pay off their credit card balance, that means that only 30% of them are using your money. So, the total amount of money you need is much less than it is for others. The money you need can come in part from the Bank of Canada, and the money consumers have in their bank accounts, on which you pay 0.75% or 1%, should be enough to cover the rest.
You said we could find out the interest rates on the Internet. I therefore did a little test. I entered the amount of $2,500 at 18%. Did you know that if consumers pay the minimum monthly amount required by the credit card company, it will take them eight and a half years to pay off the $2,500?