Does the December share price for Glaukos Corporation (NYSE:GKOS) reflect what it's really worth? Today, we will estimate the stock's intrinsic value by estimating the company's future cash flows and discounting them to their present value. This is done using the Discounted Cash Flow (DCF) model. Don't get put off by the jargon, the math behind it is actually quite straightforward.

We generally believe that a company's value is the present value of all of the cash it will generate in the future. However, a DCF is just one valuation metric among many, and it is not without flaws. Anyone interested in learning a bit more about intrinsic value should have a read of the Simply Wall St analysis model.

Check out our latest analysis for Glaukos

### The model

We use what is known as a 2-stage model, which simply means we have two different periods of growth rates for the company's cash flows. Generally the first stage is higher growth, and the second stage is a lower growth phase. To start off with, we need to estimate the next ten years of cash flows. Where possible we use analyst estimates, but when these aren't available we extrapolate the previous free cash flow (FCF) from the last estimate or reported value. We assume companies with shrinking free cash flow will slow their rate of shrinkage, and that companies with growing free cash flow will see their growth rate slow, over this period. We do this to reflect that growth tends to slow more in the early years than it does in later years.

Generally we assume that a dollar today is more valuable than a dollar in the future, and so the sum of these future cash flows is then discounted to today's value:

#### 10-year free cash flow (FCF) forecast

2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 | 2027 | 2028 | 2029 | |

Levered FCF ($, Millions) | US$25.0m | US$72.0m | US$108.6m | US$147.8m | US$185.9m | US$220.4m | US$250.2m | US$275.2m | US$295.9m | US$313.0m |

Growth Rate Estimate Source | Analyst x1 | Analyst x1 | Est @ 50.82% | Est @ 36.09% | Est @ 25.79% | Est @ 18.57% | Est @ 13.52% | Est @ 9.99% | Est @ 7.51% | Est @ 5.78% |

Present Value ($, Millions) Discounted @ 6.7% | US$23.4 | US$63.3 | US$89.4 | US$114 | US$134 | US$149 | US$159 | US$164 | US$165 | US$164 |

*("Est" = FCF growth rate estimated by Simply Wall St)***Present Value of 10-year Cash Flow (PVCF)** = US$1.2b

We now need to calculate the Terminal Value, which accounts for all the future cash flows after this ten year period. The Gordon Growth formula is used to calculate Terminal Value at a future annual growth rate equal to the 10-year government bond rate of 1.7%. We discount the terminal cash flows to today's value at a cost of equity of 6.7%.

**Terminal Value (TV)**= FCF_{2029} × (1 + g) ÷ (r – g) = US$313m× (1 + 1.7%) ÷ 6.7%– 1.7%) = US$6.4b

**Present Value of Terminal Value (PVTV)**= TV / (1 + r)^{10}= US$6.4b÷ ( 1 + 6.7%)^{10}= US$3.4b

The total value, or equity value, is then the sum of the present value of the future cash flows, which in this case is US$4.6b. The last step is to then divide the equity value by the number of shares outstanding. Relative to the current share price of US$56.4, the company appears quite undervalued at a 47% discount to where the stock price trades currently. Remember though, that this is just an approximate valuation, and like any complex formula - garbage in, garbage out.

### The assumptions

We would point out that the most important inputs to a discounted cash flow are the discount rate and of course the actual cash flows. If you don't agree with these result, have a go at the calculation yourself and play with the assumptions. The DCF also does not consider the possible cyclicality of an industry, or a company's future capital requirements, so it does not give a full picture of a company's potential performance. Given that we are looking at Glaukos as potential shareholders, the cost of equity is used as the discount rate, rather than the cost of capital (or weighted average cost of capital, WACC) which accounts for debt. In this calculation we've used 6.7%, which is based on a levered beta of 0.910. Beta is a measure of a stock's volatility, compared to the market as a whole. We get our beta from the industry average beta of globally comparable companies, with an imposed limit between 0.8 and 2.0, which is a reasonable range for a stable business.

### Next Steps:

Although the valuation of a company is important, it shouldn’t be the only metric you look at when researching a company. The DCF model is not a perfect stock valuation tool. Rather it should be seen as a guide to "what assumptions need to be true for this stock to be under/overvalued?" If a company grows at a different rate, or if its cost of equity or risk free rate changes sharply, the output can look very different. What is the reason for the share price to differ from the intrinsic value? For Glaukos, I've compiled three essential factors you should look at:

**Financial Health**: Does GKOS have a healthy balance sheet? Take a look at our free balance sheet analysis with six simple checks on key factors like leverage and risk.**Future Earnings**: How does GKOS's growth rate compare to its peers and the wider market? Dig deeper into the analyst consensus number for the upcoming years by interacting with our free analyst growth expectation chart.**Other High Quality Alternatives**: Are there other high quality stocks you could be holding instead of GKOS? Explore our interactive list of high quality stocks to get an idea of what else is out there you may be missing!

PS. Simply Wall St updates its DCF calculation for every US stock every day, so if you want to find the intrinsic value of any other stock just search here.

*If you spot an error that warrants correction, please contact the editor at editorial-team@simplywallst.com. This article by Simply Wall St is general in nature. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. Simply Wall St has no position in the stocks mentioned.**We aim to bring you long-term focused research analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Thank you for reading.*