What it means
Capital expenditure is the largest discretionary use of cash for most businesses and the one most closely tied to their future. A company that generates enough operating cash to pay for its investment is funding its own future; one that does not is funding it from lenders and shareholders, which is sustainable only if the investment produces returns that justify the capital raised.
The ratio makes the relationship explicit. Operating cash flow of $50 million against capital expenditure of $25 million is a ratio of 2.0: the company funds its investment twice over and has $25 million left.
Operating cash flow of $50 million against capex of $80 million is a ratio of 0.6: the company must find $30 million elsewhere. Neither is inherently good or bad.
A mature business with a ratio of 2.0 may be under-investing; a growth business with a ratio of 0.6 may be building capacity that will lift cash flow for a decade. The ratio prompts the question and the context answers it.
Interpretation uses several reference points. Against 1.0, the self-funding threshold.
Against the company's own history, since a falling ratio means investment is outrunning cash generation or cash generation is falling behind investment needs. Against depreciation, because capex below depreciation for several years usually means the asset base is shrinking regardless of the ratio.
Against peers, since capital intensity varies by industry: utilities and telecoms commonly run ratios around 1.0 to 1.3 through long investment cycles, while software companies run ratios of 5 or more. And against the split of capex between maintenance and expansion, because a ratio below 1.0 caused by expansion is a choice while one caused by maintenance is a constraint.
For lenders the ratio is part of the assessment of debt capacity: a company whose operations cover its capex has cash available for debt service; one whose capex exceeds operating cash flow is adding to its borrowing need every year. Rating agencies track it as a component of financial policy.
For boards the ratio, projected over a capital programme, shows how much external funding the programme requires and for how long, and is often used to set a policy such as "capex funded from operating cash flow over a rolling three-year period, with acquisitions funded separately". The measure has limits.
It ignores debt service and dividends, which also claim operating cash flow, so a ratio comfortably above 1.0 does not mean the company is self-funding overall; the cash flow adequacy ratio covers that. Capex is lumpy, so single years mislead.
And a very high ratio may indicate a business that has stopped investing rather than one generating exceptional cash.
In practice
Real-world examples.
Example
A software company's ratio of 8.0 reflects minimal capital needs; its investment goes through the income statement as development expense.
Example
A mining company's ratio falls to 0.4 during a three-year mine development and rises to 3.0 once the mine is producing.
Example
A retailer with a ratio of 1.1 and capex below depreciation is challenged by analysts to explain how it will refurbish its ageing stores.
Think of it
“This ratio shows whether your business throws off enough cash to fund its own growth investments.
Formula
Calculation
Cash Flow to Capital Expenditure = Operating cash flow / Capital expenditure
Capex as % of Operating Cash Flow = Capital expenditure / Operating cash flow x 100%
Surplus (or shortfall) after capex = Operating cash flow minus Capital expenditure = Free cash flow
Worked example. A regional airline reports over four years:
- Year 1: operating cash flow $95,000,000; capex $60,000,000 (two replacement aircraft and engine overhauls); depreciation $55,000,000. Ratio 1.58; free cash flow $35,000,000.
- Year 2: operating cash flow $102,000,000; capex $180,000,000 (four new aircraft for route expansion); depreciation $58,000,000. Ratio 0.57; shortfall $78,000,000, funded by $90,000,000 of aircraft finance.
- Year 3: operating cash flow $118,000,000; capex $170,000,000 (three more aircraft); depreciation $68,000,000. Ratio 0.69; shortfall $52,000,000, funded by debt.
- Year 4: operating cash flow $140,000,000; capex $65,000,000 (the expansion complete; maintenance level); depreciation $75,000,000. Ratio 2.15; free cash flow $75,000,000, of which $50,000,000 repays debt.
Reading: years 2 and 3 show the airline investing far beyond its cash generation to expand its fleet, funded by $150,000,000 of new debt. The test of that decision is year 4: operating cash flow has risen from $95,000,000 to $140,000,000, a 47% increase, and the ratio has returned above 2.0 with capex at maintenance level, so the expansion is paying for itself and the debt is being repaid. Had year 4 operating cash flow stayed at $100,000,000, the ratio would still have recovered (capex having fallen) but the airline would be carrying $150,000,000 of extra debt with no extra cash flow to service it.
Four-year cumulative: operating cash flow $455,000,000; capex $475,000,000; ratio 0.96. Over the whole investment cycle the airline was almost self-funding, which is the number the board's policy is set on: capex covered by operating cash flow over a rolling four-year period.
Maintenance test: depreciation over the four years totalled $256,000,000; the airline's own estimate of maintenance capex was $240,000,000; expansion capex was therefore $235,000,000, funded by the $150,000,000 of debt and $85,000,000 of operating cash flow.
Peer comparison: a competitor reported a ratio of 1.8 in every year of the same period and no fleet growth; its aircraft averaged 14 years old against the first airline's 8, and its fuel and maintenance costs per seat were 12% higher. Its high ratio was the arithmetic of not investing.Case study
Seen in the real world.
A chain of private hospitals had, for six years, reported a cash flow to capex ratio between 2.0 and 2.5 and had used the surplus for acquisitions and dividends. Its board took the ratio as evidence of strong cash generation. A newly appointed non-executive director, a former hospital operator, asked for capex against depreciation: capex had averaged $30 million a year against depreciation of $55 million.
The hospitals' equipment was ageing, two had building systems past their design life, and the group's clinical outcome scores had slipped from the top quartile to the median. The board commissioned a survey that identified $280 million of deferred maintenance and replacement, about nine years of the recent capex level.
The following three years' capex was $110 million a year, the ratio fell to 0.8, the dividend was cut and two acquisitions were deferred. The non-executive's note to the board observed that the ratio had been high because the denominator had been too small, and that a business which spends half its depreciation on capital for six years has been paying its dividends out of its buildings.
Watch out
Common mistakes.
- Treating a high ratio as strength without checking capex against depreciation. Under-investment produces a high ratio and a deferred bill.
- Reading a low ratio as weakness without distinguishing expansion from maintenance capex, and without looking at the cash flow the expansion later produces.
- Assessing single years. Capital programmes run over several years; use a rolling three- to five-year cumulative ratio.
Questions
People also ask.
What is a good cash flow to capex ratio?
Above 1.0 over a cycle means the business funds its own investment. The right level depends on the industry's capital intensity and the company's growth phase; comparison with peers and with depreciation gives it meaning.
How does this ratio differ from free cash flow?
Free cash flow is the difference (operating cash flow minus capex); this ratio is the quotient. They carry the same information; the ratio is easier to compare across sizes.
Does the ratio include acquisitions?
Usually not: capital expenditure means purchases of property, plant, equipment and intangibles. Acquisitions are analysed separately, since they are discretionary and lumpy.
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