What it means
A ratio simply divides one financial figure by another to make the result comparable across time and across companies. Revenue of $8,000,000 tells you little on its own, but gross profit of $3,200,000 on that revenue gives a margin of 40%, which can be compared with last year and with a competitor.
That comparability is the whole point. Key ratios are usually grouped into four families.
Liquidity ratios such as the current ratio ask whether short-term bills can be paid; profitability ratios such as gross margin and return on capital employed ask whether the business earns enough on what it does; efficiency ratios such as inventory turnover and days sales outstanding ask how hard the assets are working; and gearing ratios such as debt to equity ask how much of the risk sits with lenders. The word "key" means the selection is deliberate.
A subscription software business will treat gross margin and net revenue retention as key, while a haulage firm cares about revenue per vehicle and fuel as a percentage of revenue. Applying one company's key ratios to another sector produces confident but meaningless conclusions.
Lenders formalise the idea in covenants, where a loan agreement specifies that named ratios must stay within limits, tested quarterly. Breaching one can make a loan repayable on demand, which is why finance teams model covenant headroom before signing anything.
The main nuance is that ratios describe rather than explain. A current ratio falling from 1.8 to 1.1 signals pressure, but only the underlying detail tells you whether that is a supplier squeeze, a stock build or a customer who has stopped paying.
Treat a key ratio as the question, not the answer.
In practice
Real-world examples.
Example
A garden centre chain watches inventory turnover as its key efficiency ratio. When turnover falls from 6.0 to 4.5 times a year, the buying team cuts orders of slow-moving stock before the winter cash squeeze arrives.
Example
A civil engineering contractor reports return on capital employed to its board every quarter, because plant is expensive and the ratio shows whether the machines are earning their keep. A drop below 12% triggers a review of hire rates.
Example
A family-owned hotel group is required by its bank to keep interest cover above 3.0 times. Before agreeing a refurbishment loan, the finance director models the new interest cost and confirms cover would still sit at 3.4 times.
Formula
Calculation
Each key ratio has its own formula. Taking liquidity as the example: current ratio = current assets / current liabilities, and quick ratio = (current assets - inventory) / current liabilities.
A wholesale food business has current assets of $2,400,000, of which $900,000 is inventory, and current liabilities of $1,600,000. Current ratio = $2,400,000 / $1,600,000 = 1.5, meaning it holds $1.50 of short-term assets for every $1.00 of short-term obligations.
Quick ratio = ($2,400,000 - $900,000) / $1,600,000 = $1,500,000 / $1,600,000 = 0.94. Stripping out stock that cannot be sold instantly, the business is slightly short of covering its immediate bills.
The lender's covenant requires a current ratio of at least 1.25. Headroom is 1.5 - 1.25 = 0.25, and since current liabilities are $1,600,000, the covenant would be breached if current assets fell below 1.25 x $1,600,000 = $2,000,000, a drop of $400,000. That single number is far more useful to a finance director than the ratio alone.Case study
Seen in the real world.
This account is illustrative and fictional. Larkspur Textiles, a mid-sized fabric supplier, reported growing revenue of $12,000,000 and a comfortable-looking net profit of $780,000, so its founders saw no reason for concern.
Their bank looked at two key ratios instead. Days sales outstanding had crept from 48 days to 79 days, and the current ratio had fallen from 1.9 to 1.2 as the overdraft grew. Working from those figures, the receivables balance had risen from roughly $1,578,000 to about $2,597,000, tying up more than $1,000,000 of extra cash despite a healthy profit line.
Larkspur's fictional recovery came from acting on the ratios rather than the profit figure. It introduced 30-day terms for new accounts, offered a 2% early settlement discount and cleared slow stock, bringing days sales outstanding back to 55 days and restoring the current ratio to 1.6 within three quarters.
Watch out
Common mistakes.
- Comparing a ratio against a general rule of thumb rather than against the norms for that specific industry.
- Reading a single ratio in isolation, when liquidity, profitability and gearing only make sense together.
- Recalculating ratios inconsistently between periods, for example including a new lease liability one year and not the next, which makes the trend meaningless.
Questions
People also ask.
How many key ratios should a business monitor?
Most companies manage with five to eight, chosen to cover liquidity, profitability, efficiency and gearing.
Is a higher ratio always better?
No, an unusually high current ratio can mean idle cash or excess stock, so each ratio has a sensible range rather than a simple direction.
Where do the input figures come from?
The income statement and balance sheet, which is why consistent accounting policies matter more than the arithmetic itself.
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