Enron, WeWork, the frauds Muddy Waters exposed — every one of them reported positive "net income" while cash flow was deeply negative. Accounting profit (Net Income) is an adjustable number, shaped by depreciation, the timing of revenue recognition, and one-off valuation gains. Free Cash Flow (FCF) is the cash that actually remains in the company's bank account — and it is almost impossible to adjust. That is the real reason Warren Buffett looks at P/FCF (or Owner Earnings) rather than PER.
The most common formula:
Both numbers are pulled straight from the company's Cash Flow Statement — real money that actually moved in and out, with none of the estimates or assumptions baked into accounting profit. CapEx is the "capital invested to sustain or grow the business" — factories, equipment, stores.
A variant: Owner Earnings (Warren Buffett's definition) = Net Income + Depreciation − Maintenance CapEx (growth CapEx is excluded). More conservative than FCF, since it also deducts growth investment.
Shifting the timing of revenue recognition, tweaking depreciation periods, adding one-off valuation gains, booking reserves — all of these can legally inflate net income. An audit only reviews whether such adjustments are "reasonable."
A bank balance can't lie. Negative FCF = the business is burning cash = it will eventually have to plug the gap with debt or a share issue = dilution of shareholder value.
Dividends and share buybacks are both cash — you can't pay them out of net income. A company's ability to keep returning capital to shareholders exists only when FCF is reliably positive.
Tesla — net income was in the red through 2019, but FCF turned steadily positive from 2020 → that moment was the real break-even of the business model. The stock rose 5× shortly after.
If PER answers "how many times accounting profit is the price I paid," P/FCF answers "how many times actual cash is the price I paid." More conservative and more trustworthy.
| Metric | Valuation range (rough) |
|---|---|
| P/FCF < 10 | Possibly undervalued (or a business in trouble) |
| 10 ~ 20 | Normal range — most quality companies |
| 20 ~ 30 | Reflects high growth expectations |
| > 30 | Possible bubble — future FCF really has to explode to justify it |
Deliberately deferring CapEx inflates short-term FCF (aging equipment → future losses). Look at a 3–5 year average for stability. Also, a young growth company (Amazon 1997–2001) can have CapEx larger than revenue, making FCF negative → which on its own tells you nothing about value.
The most useful application: when the same company's PER and P/FCF differ sharply, that difference is the starting point of your analysis.
Among Korean listed companies, the accounting-fraud cases (e.g. Daewoo Shipbuilding 2015, Asiana 2019) all showed a large gap between PER and P/FCF beforehand.
Today Multifolios is centered on price-based tracking (price / return / valuation), and does not provide fundamental metrics (FCF / PER / ROIC, etc.). The reasons:
Instead, we support short-term monitoring focused on the macro environment (market sentiment / VIX / FX) plus the technical side (moving averages). For fundamentals like FCF, we recommend using external tools (e.g. Macrotrends, Stockanalysis.com) at the buy-decision stage.
Net income can be adjusted by accounting; FCF is actual cash. P/FCF is more robust than PER against accounting fraud and fake profits. When the two metrics diverge sharply, that is where your analysis begins.