Tuesday, December 26, 2006

Discounted Cash Flow or DCF

Discounted Cash Flow or DCF is the most complicated way to value a stock and also probably quite useless to most people. Well, not if you are good at math or if you are called Buffett or Graham or Dodd. Buffett uses very simplified DCF to try to value stocks and is probably quite good at it, given how much he has earned (umm, in case you don't know, it's about 1/3 of what the whole of Singapore earns). Too bad he doesn't blog.

Well I guess I would just try to describe the concept of DCF, bcos the math will simply freak out a lot of people. But having said that, it's probably A level or 1st year university math so if you really want to know, can google it and try to figure it out.

Ok the concept is basically adding up all the cashflow over the life of the firm and try to determine how much it is today.

Perhaps it is easier to use an example:

Firm A will generate $1 of cashflow over the next 50 yrs, what is its value (or intrinsic value) today?

Well the simple answer is simply $1 x 50 = $50 (QED).

Ok, but how can be so simple?

Now we must understand that $1 next year is not the same as $1 today. And $1 two years out is also different. The difference is due to interest.

So $1 next year is actually equal to $0.97 today bcos if we put $0.97 in the bank today, it will earn 3% interest and become $1 next year. And $1 two years out is roughly $0.93 today bcos if we put $0.93 into the bank today, it will earn 3% interest in 1 yr, and both the interest and principal after Year 1 will earn another 3% interest, which brings the total to $1 two years from now.

So once we calculated the present value of all those future $1 (50 of them), we add them all up and we get the intrinsic value of the firm. For the above example, the answer is $25.7.

If you are wondering how to get $25.7, key this "=PV(3%,50,1,0)" in Excel and it will spit out the answer. Need more help, pls email me.

Well, not so hard after all I guess. But the questions below will make you realize what makes it hard.

First, how the hell do we know if Firm A can actually earn $1 every year for the next 50 yrs? And what will the interest rate be in 50 yrs time? And why only 50 yrs, shouldn't a company exist longer than that?

So that's the hard part, for every input, there is some uncertainty. With DCF, you can have infinite no. of inputs, and that's uncertainty times infinity. How fun. Personally I prefer to stick with PER and EPS estimates.

See also Intrinsic Value Part 2
and Definition: Value Investing
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