To give just one example, on-demand ride startup Lyft recently sold a batch of stock that increased the company&#x27;s implied value to $5.5 billion. The amount is eye-popping for a not quite 4-year-old company that is spending far more money that it generates, and reported a relatively slim $47 million in revenue for the first six months of 2015, my colleagues Eric Newcomer and Alex Barinka have reported. To show how outlandish Lyft’s valuation is, consider that on a roughly similar basis Apple would have a stock market value of more than $12 trillion, about two-thirds of the annual gross domestic product of the U.S.<p>Can someone ELI5 what a &quot;roughly similar basis&quot; might be? How did they arrive at this number?