Oscar Health

For years Oscar grew quickly while losing money. That has changed. Revenue reached about 15.3 billion dollars, growing 27.5 percent over the past year, and the company is now genuinely profitable with margins of 3.6 percent. In insurance, where margins are thin by nature, crossing from loss into profit is the hardest step.

Despite growing revenue more than 27 percent, the shares trade at roughly 16 times earnings. That is an ordinary price for a company growing at well above ordinary speed. Its technology platform also means each new member costs less to serve than at a traditional insurer.

Oscar depends heavily on the public marketplaces, and those depend on government subsidies that make the plans affordable. If subsidies are reduced, some members simply cannot pay and the pool of customers shrinks. This is a fast growing company operating in a market whose size is decided politically.

The shares move well over twice as hard as the market. Insurance profits can also swing sharply if members turn out to be sicker than expected in a given year, and with margins of only 3.6 percent it does not take much of a miss to wipe out the profit entirely.