Not investment advice. Educational reading. See Disclaimer.
L.5 · INTERMEDIATE · 2 MIN
Sensitivity Analysis: Stress-Testing Your DCF
Every DCF should include a sensitivity table showing how valuation changes with different assumptions. A good analyst presents a range, not a point estimate. The ‘margin of safety’ concept from Benjamin Graham is the gap between your intrinsic value and the market price.
If your target price only works with a specific WACC and growth rate combination, you’re speculating, not investing. Look for companies where most of the sensitivity table shows upside — that’s a genuine margin of safety.
§ 03Step through
The best DCF analysts also run scenario analysis: What if the company loses its biggest customer? What if a new competitor enters? What if regulation changes? Assign probabilities and probability-weight the outcomes.
Scenario
Probability
Value/Share
Weighted
Bull
25%
$120
$30
Base
50%
$80
$40
Bear
25%
$45
$11.25
Expected
100%
$81.25
§ 04Try it
Build a simple sensitivity table for a company you’re analyzing. Vary WACC from 8–12% and terminal growth from 1.5–3%. How wide is the range?
§ 05Check-in
Your sensitivity table shows a range of $55–$135 per share. The stock trades at $70. Is this a buy?
§ 06Key insight
The sensitivity table is the most honest part of a DCF. It shows you what you’re really betting on and how wrong you can be before losing money. If the stock price is above most of the table, walk away.
§ 07Check-in
Your DCF intrinsic value is $150/share. You ran sensitivity on WACC (±1%) and terminal growth (±0.5%). Range: $110-$210. Stock trades at $125. Decision?
Check your understanding
●○○○○
Sit with the ideas.
Your base case DCF gives a value of $120/share. Your bull case (lower WACC, higher growth) gives $180. Your bear case (higher WACC, lower growth) gives $75. The stock trades at $95. What is the most prudent conclusion?