What it means
A lender's assets are mostly the loans it has made, so the quality of those loans is the quality of the business. A loan is generally classed as non-performing once payments are more than ninety days overdue, or once the lender no longer expects to be repaid in full.
The ratio simply asks what share of the book sits in that category. The number matters because loans are carried on the balance sheet at close to full value until something forces a write down.
A bank reporting healthy profits while its non-performing ratio climbs is usually reporting profits it will hand back later through provisions, which are amounts set aside for expected losses. Regulators and analysts read the ratio alongside the coverage ratio, which compares provisions already taken against the non-performing balance.
A 4% non-performing ratio with 90% coverage is a very different situation from the same 4% with 30% coverage, because in the first case most of the pain has already been recognised. Non-financial businesses use the same idea under different names.
A company with a large trade receivables book tracks the percentage of debts more than ninety days overdue, and a subscription business tracks failed payments, both for exactly the same early warning purpose. Two nuances catch people out.
The ratio can fall simply because the lender wrote off bad loans or grew the denominator with new lending, neither of which means the existing book improved, so the trend needs reading alongside gross lending volumes and write off activity. Definitions also vary between jurisdictions and between institutions, particularly on when a restructured loan returns to performing status.
Comparing two lenders demands a quick look at how each one defines the numerator before drawing any conclusion from the difference.
In practice
Real-world examples.
Example
A credit union sees its ratio drift from 1.8% to 3.1% over four quarters and tightens lending criteria on used vehicle finance, which is where almost all of the increase originated.
Example
An investor comparing two banks with similar profits notices one reports 2% non-performing loans with 80% coverage and the other 2% with 25% coverage, and treats the second as carrying far more unrecognised loss.
Example
An equipment leasing company applies the same logic to its own book, tracking the percentage of contracts more than ninety days in arrears as its main early warning indicator.
Think of it
“Asset quality ratio shows what percentage of your assets are performing well-portfolio health.
Formula
Calculation
Asset quality ratio = non-performing loans / total gross loans x 100. The related coverage ratio = loan loss provisions / non-performing loans x 100.
A regional lender has total gross loans of $2,400,000,000 and non-performing loans of $84,000,000. The asset quality ratio is $84,000,000 / $2,400,000,000 x 100 = 3.5%, meaning three and a half cents in every dollar lent is not being repaid on schedule.
The same lender holds loan loss provisions of $63,000,000. Its coverage ratio is $63,000,000 / $84,000,000 x 100 = 75%, so three quarters of the problem balance has already been recognised as a likely loss. The remaining $84,000,000 - $63,000,000 = $21,000,000 is the exposure still to be absorbed if those loans recover nothing.Case study
Seen in the real world.
This is an illustrative and entirely fictional example. Meridian Coast Bank, an invented regional lender, grew its commercial property book by 40% in two years and reported a falling asset quality ratio throughout, from 2.4% down to 1.7%.
The improvement was arithmetic rather than real. In the fictional scenario the non-performing balance had actually risen in dollar terms, but the denominator of new lending grew faster, so the percentage fell. When growth stopped, the ratio jumped to 5.9% within three quarters as the newest loans seasoned and the older problems remained.
Meridian's illustrative lesson is to read the ratio in dollars as well as per cent, and to watch the ratio for each loan vintage separately. A book growing quickly will always flatter its own asset quality until the growth stops.
Watch out
Common mistakes.
- Reading a falling ratio as an improving book when the fall is caused by rapid new lending inflating the denominator.
- Looking at the non-performing percentage in isolation without checking how much of it has already been provided for.
- Comparing the ratio across countries or lender types without checking that each defines non-performing the same way.
Questions
People also ask.
What counts as a good asset quality ratio?
It varies by lender and market, but low single digit percentages are typical for mainstream lenders while specialist high risk lending naturally runs higher.
Does writing off a bad loan improve the ratio?
Yes mechanically, because the loan leaves both the non-performing balance and the total book, which is why write off activity should be read alongside the ratio.
Can a business without loans use this measure?
Yes, the same calculation applied to trade receivables more than ninety days overdue gives a comparable early warning signal.
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