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Blog Deep-Read · 22 · aswathdamodaran.blogspot.com

Aswath Damodaran
Price and value are two different games, and most arguments happen between them

Musings on Markets · 682 posts · opened 17 September 2008, two days after Lehman Brothers collapsed · roughly fifty posts a year from 2008 to 2016, settling at twenty-odd a year from 2017 · latest post 10 September 2026, still active · entirely free, no paywall · this page is based on 17 posts read in full, spanning September 2008 to August 2026, four of them inside the earliest 20% of the blog's lifespan · the blog has no author-curated "best of" page, so the reading list was built from in-site backlink centrality (ranked by how many distinct later years cite a post, with intra-series cross-links discarded), then topped up with outside attention and a period quota

In the summer of 2015, a finance professor at NYU did a very dumb piece of arithmetic.

He listed the public companies that lived off online advertising — Google, Facebook, Twitter, LinkedIn, Yelp — and then did something backwards to each one. Instead of estimating what the company was worth, he took its market value as given and solved for the number the market must be assuming: how much advertising revenue does this company have to collect every year, ten years out, for today's price to make sense? For Facebook the answer came out at $117.7 billion.

Then he added the whole column up: $523 billion.

Then he went and found a second number — the largest the global online advertising market could plausibly be in ten years. His assumptions were generous: total advertising grows with the economy, and online climbs to half of all advertising. The answer was $466 billion.

Which is to say: the revenue quietly promised to these few listed companies already exceeded the entire market ten years out. That is before counting the private companies queuing up to list, and before counting everyone else who sells an ad on the side.

There is no liar anywhere in this picture. Each company's price, taken on its own, is defensible. The absurdity lives only in the sum.

The man doing the arithmetic is Aswath Damodaran, born in Chennai in 1957, teaching valuation at NYU's Stern School of Business since 1986. His blog is called Musings on Markets, subtitled "My not-so-profound thoughts about valuation, corporate finance and the news of the day!" It opened on 17 September 2008 — two days after Lehman Brothers went under. The first sentence of the first post is: "I must confess that I have mixed feelings about blogs."

Eighteen years and 682 posts later, if you had to compress this mind into one line, it would be: "what is this thing worth" and "what will someone pay for it" are two different questions, and most arguments in markets are two groups answering different questions while each is convinced the other is talking nonsense.

He calls the two things the value game and the pricing game. Value is set by fundamentals: cash flows, growth, risk. Price is set by supply and demand: mood, momentum, what everyone else is doing. People who play the first are investors; people who play the second are traders.

What matters is that he refuses to look down on the traders. He wrote a line few professors would write: a trader who makes a million dollars can buy exactly as much with it as an investor who makes the same million. What he actually objects to is blur — people who talk value while watching momentum, or the reverse.

Stealing from the title of the bestseller from a few years ago, if traders are from Venus, investors are from Mars, and if one is talking about price and the other about value, they may both be right, even with vastly different numbers. Twitter can be a good trade and a bad investment at exactly the same time!Twitter IPO: Why a good trade be a bad investment (or vice versa)?, 10 October 2013

Once you see the split, a lot of awkward things go smooth. A great company can be a bad investment, if the price is high enough. A terrible company can be a good investment, if the price is low enough. In 2017 he ran the excess returns of every listed company on earth: 19,960 were destroying value, only 10,947 were creating it — roughly two in three of the world's public companies are, by his measure, bad businesses.

But the best part of this mind is not that conclusion. It is watching him take a beating with it.

June 2014: venture investors price Uber at $17 billion. He works it out and gets $5.9 billion, and posts the spreadsheet so anyone can change his numbers. Silicon Valley erupts. Bill Gurley — Uber board member, Benchmark partner — writes a rebuttal titled "How to Miss By a Mile," and his central blow lands on the deepest assumption: by using the historical size of the taxi market as your base, you are quietly assuming the future looks like the past. A billion cars worldwide, $6,000 a year to own one: that's a $6 trillion market for not having to own a car.

Most people would start arguing here. What Damodaran did was re-run the same machine using Gurley's story, get $54 billion, and thank him in public.

Value investors then attacked him from the other side: how can a number jump from $6 billion to $54 billion? His answer was that this is exactly what you should expect. Numbers don't fall from the sky; numbers are translated stories. Change the story and the number has to move. He later compressed this into the line he quotes back to himself more than any other:

I have long believed that a company valuation without a story to bind it together is just numbers on a spreadsheet and a story that uses no numbers at all is a fairy tale.DCF Myth 3: You cannot do a valuation, when there is too much uncertainty!, 2 May 2016

This is not splitting the difference. It is a specific machine: break the story into a handful of falsifiable dials — how big is the market, what share can you take, what slice do you keep, how much capital does the growth eat — and then turn the dials and watch value move. In December 2014 he went further and shipped a build-your-own-Uber template: pick your own parameters, and the answers ranged from under $1 billion to nearly $100 billion.

As for what to do when you genuinely cannot see, his answer runs against instinct: the more uncertain it is, the simpler the model gets. Not more decimals, not more line items — cut it down to three variables. He says there is a voice in his head shouting that he is going to be badly wrong, and he silences it like this:

I don't have to be right, just less wrong than everyone else, and that when uncertainty is rampant, most investors give up.DCF Myth 3, 2 May 2016

The same post ends: I am wrong a hefty percent of the time, but so what? It's only money. I'm just glad I'm not a brain surgeon.