The calculation formula of NPL ratio is as follows:

Non-performing loan ratio = (subprime loan+doubtful loan+loss loan)/loan * 100%= loan provision ratio/provision coverage ratio * 100%.

The general non-performing loan ratio refers to the proportion of non-performing loans of financial institutions to the total loan balance. When evaluating the quality of bank loans, loans are usually classified according to risks, which are mainly divided into five categories: normal, concerned, secondary, suspicious and loss. Among them, subprime loans, doubtful loans and losses are collectively referred to as non-performing loans.