The Reinvestment Rate: The Hidden Superpower of Compounders

Two companies can have the same ROIC and the same revenue growth, yet one creates far more value for shareholders. The difference is the reinvestment rate — how much of their profits they can reinvest at high returns.

What Is the Reinvestment Rate?

The reinvestment rate is the proportion of earnings that a company keeps and reinvests in the business rather than paying out as dividends or buying back shares. A company that earns $100 million and reinvests $60 million has a reinvestment rate of 60%.

The reinvestment rate by itself tells you nothing. You also need to know the return on that reinvested capital. A company reinvesting 60% of earnings at 20% ROIC is a compounding machine. A company reinvesting 60% at 5% ROIC is destroying value.

The magic formula: expected earnings growth = reinvestment rate × ROIC. A company reinvesting 50% of earnings at 20% ROIC will grow earnings at 10% per year — automatically, without any improvement in the underlying business.

Why Some Companies Cannot Reinvest

Not every company can reinvest large amounts of earnings at high rates. The limiting factor is not willingness — it is opportunity. A company with a wide moat in a mature industry might generate enormous profits but have few places to invest them.

Think of a premium consumer brand like Coca-Cola. It generates billions in profits but cannot reinvest all of them at high returns because the market for soda is not growing fast enough. The best use of that cash is to return it to shareholders through dividends and buybacks.

This is not a flaw. It is a sign of a maturing business. But it means the company's earnings will grow slower than its ROIC suggests. The reinvestment rate reveals the gap between profitability and growth potential.

The Ideal Combination

The best compounders sit in a sweet spot: they generate high ROICs AND have plenty of opportunities to reinvest at those high rates. These companies can grow earnings at 15-20% per year for decades without needing debt or issuing new shares.

Software companies are the classic example. They earn high returns on capital and have massive addressable markets. They can reinvest most of their profits into product development and sales, generating more revenue and more profits to reinvest again. This flywheel is what makes software the ultimate compounder business model.

How to Use This

When evaluating a company, ask two questions. First, how much of its earnings is it reinvesting? Second, what return is it earning on that reinvested capital? If both numbers are high, you have found a potential compounder. If one is low, the company's growth will be limited regardless of how profitable it is.