Discounted Cash Flow (DCF) Valuation Explained: GOOGL and MSFT Case Studies
A practical guide to DCF valuation, focusing on why small changes in growth and discount rate assumptions drive massive swings in intrinsic value.
What it means
A Discounted Cash Flow (DCF) analysis estimates the intrinsic value of an asset by projecting future free cash flows and discounting them to the present. This method accounts for the time value of money and the specific risk profile of the business.
Michael Mauboussin notes that while investors often criticize DCF for its reliance on assumptions, alternative methods like P/E multiples simply hide those same assumptions behind a single, opaque number. Using a DCF forces you to explicitly define what you believe about a company's future growth and risk.
- Valuing stable, cash-generative businesses where future cash flows are predictable.
- Determining intrinsic value independent of current market sentiment or comparable company multiples.
- Conducting reverse DCF analysis to understand what growth or margin assumptions the current market price implies.
How it's calculated
The calculation requires projecting cash flows over a specific period, usually 5 to 10 years, and then calculating a terminal value to represent all cash flows beyond that horizon. These figures are then discounted back to today using a rate that reflects the cost of capital.
The model is highly sensitive to input variables. Small adjustments to these core components can lead to vastly different valuation outputs.
- Free Cash Flow (FCF): The cash generated by the business after accounting for capital expenditures.
- Discount Rate (WACC): The weighted average cost of capital, representing the risk-adjusted return required by investors.
- Terminal Value: The estimated value of all future cash flows beyond the projection period, often accounting for over 70% of total value.
- Terminal Growth Rate: The assumed long-term growth rate of the business, typically capped at the rate of economic growth.
Worked example
Microsoft (MSFT) provides a clear look at how terminal value assumptions drive valuation. With a market cap of $2.84 trillion and a P/E of 23.93, the company's long-term outlook is heavily weighted toward its terminal value.
If an analyst increases the terminal growth rate assumption from 2% to 3%, the terminal value can increase by 15% to 20%. This compounding effect demonstrates why terminal value assumptions are the most dangerous inputs in any model.
Alphabet (GOOGL) illustrates the impact of the discount rate. With a $3.52 trillion market cap and a P/E of 26.89, a 1% increase in the discount rate due to higher perceived risk can reduce the present value of future cash flows by 10% to 15%.
Common mistakes
Many investors treat the DCF as a black box to justify a target price rather than a tool to stress-test their assumptions. Avoiding these errors improves the reliability of the output.
Sensitivity analysis is the only way to mitigate the risk of a false sense of precision. Always test how the final valuation changes when you adjust your growth and discount rate inputs.
- Uniform growth rates: Model a transition to steady-state growth rather than using a single, constant rate for the entire projection period.
- Excessive terminal value: If the terminal value represents more than 80% of the total valuation, the explicit forecast period is likely irrelevant.
- Lack of sensitivity analysis: Always perform stress tests on the discount rate and terminal growth rate to understand the range of possible outcomes.