[Lavery]

Sorry, wrote that quickly and wasn't super clear. What I meant was ranking. The S&P 500 is what's called a "cap-weighted index", where companies are ranked 1 through 500 by market capitalization, which is share price times the number of shares outstanding. Share count isn't meaningful, because (generally) increasing share count on the same company will just decrease price, and vice versa.

In most cases a company lifecycle is like, we launched a company, it's private for a few years, then it goes public. Either shortly before going public, but maybe a few years after, it becomes profitable. It then grows and grows etc, and joins the S&P by virtue of its size getting larger than the 500th-ranked firm already in the S&P ("size" here is market cap).

Tesla is different, because Tesla went public and was unprofitable, then got ~big and was still unprofitable, and now for (largely unknown) reasons would be, if it were included, the 10th largest company in the S&P, but is still unprofitable. They may cross that threshold later this month, but this process--joining the S&P at rank 10--is highly unusual.