What is the Dual Cash Flow Screen?
The Dual Cash Flow Screen is built on a technique from Ernst Institutional Research. Harry Ernst and his longtime partner Jeffrey Fotta developed dual cash flow to separate two very different sources of a company's cash: the cash its operations actually generate, and the cash it conjures by rearranging its balance sheet. Fotta later became research director at Lindner Funds and co-manager of the Lindner Large-Cap fund, which used quantitative screens including this one to surface candidates. The screen's real promise is early warning — it can flag a company drifting toward trouble while its earnings and sales still look strong.
The core idea — two cash-flow tests, not one
Earnings can be massaged, and small accounting differences make them hard to compare across firms or track over time. Cash is harder to dress up, which is why this method leans on it. Dual cash flow splits a company's cash into two figures, each expressed as a percent of sales. Operating cash flow is roughly the change in owners' equity minus the change in growth-producing assets — property, plant and equipment, inventory, long-term investments — and it captures the cash a business throws off by operating. You want it positive and rising. Balance sheet cash flow is the change in liabilities minus the change in receivables, and it captures cash raised by borrowing more or stretching what the firm is owed. You want it negative and falling.
The reason two tests beat one: a company can post rising earnings while quietly funding itself from the balance sheet — taking on debt, delaying payments, letting receivables swell. Measuring operating generation and balance-sheet financing separately exposes that gap. One test tells you cash exists; two tell you where it came from. The best-situated firms show operating cash flow climbing while balance-sheet cash flow shrinks.
What the Dual Cash Flow Screen looks for
- Over-the-counter stocks are excluded, to keep a floor under liquidity and access to current financial statements.
- Operating dual cash flow is positive in each of the last two fiscal quarters (Q1 and Q2). It equals [(Change in Common Equity - (Change in Net Fixed Assets + Change in Inventory + Change in Long-Term Investments + Change in Goodwill & Intangibles + Change in Other Long-Term Assets)) / Sales] × 100.
- Balance sheet dual cash flow is negative in each of the last two fiscal quarters (Q1 and Q2). It equals [(Change in Liabilities + Change in Preferred Stock - Change in Accounts Receivable) / Sales] × 100.
- Dual cash flow has increased quarter over quarter across each of the last four fiscal quarters, where dual cash flow equals operating dual cash flow minus balance sheet dual cash flow.
Why it can work
Cash flow reflects a company's true operating performance and sidesteps the comparability problems that dog reported earnings. Ernst and Fotta argued that the operating-versus-balance-sheet split gives an early read on where earnings are headed, up or down, and they used it to judge individual stocks and the market as a whole. The model treats a swelling cash balance as the growth of an unproductive asset and penalizes firms that reach for the balance sheet to paper over weak operations. What survives tends to be businesses whose reported growth is backed by cash they actually earned rather than borrowed.
What to keep in mind
This is a quality and red-flag screen, not a valuation screen — it says nothing about whether a stock is cheap, so it needs to be paired with work on price. Dual cash flow is also uncommon and data-heavy: it is not a standard line item, it takes custom fields to build, and quarter-to-quarter figures can be noisy. The method rests on a growth-versus-liquidity trade-off that can misread a fast-growing firm legitimately investing ahead of demand, since such a company consumes cash on purpose. Treat a pass as a reason to look closer, not a buy signal.
Sources
Dual cash flow methodology developed by Harry Ernst and Jeffrey Fotta, Ernst Institutional Research; later applied in quantitative screening at Lindner Funds.
American Association of Individual Investors (AAII) — Stock Investor Pro screen definition and commentary.