You are right, cash yield doesn't tell the whole story BUT it is the only data available to public investors. No public investor has had access to any projections, detailed operating metrics, access to growth drivers and no real information on the use of the IPO proceeds. The stock market is not a place for pure startups. Startups is an asset class that should only be for angel investors, VCs, and other niche funds. If you are selling me the startup story, I want startup returns, i.e. for each $20/share I buy I want to have the "certainty" I will be able to make $200/share in 3 to 5 years. Consequently $200/share is an implied $127bn market cap. Can you see how weak that "Groupon is a startup" argument is?

Having said that, Groupon is not a startup: 7,000+ employees, over $500m in revenues, considerable international presence, large M&A transactions, etc. This kind of company should be be valued using a DCF. Growing at 100% per annum is no excuse to be able to perform such exercise. The devil is in the detail, and trying to find excuses to argue that Groupon is a startup, and consequently valuing it by god knows what random vanity metric is not a valid argument.

Can you give me a data based argument/point that shows that Groupon is not overpriced at $20/share? I have given you one.

Bottom line: all I'm saying is that Groupon should be valued fairly, $20/share is not a fair value, it's overpriced. Investors are left with no upside. I'm not saying that Groupon hasn't got a valid business.