So while we should always try to assess where a stock or sector is headed, the better way to trade is with a simple framework: Any stock can go up and thus be a source of profits. However, owning each stock comes with different levels of risk,

Berkshire Hathaway's latest regulatory filing revealed that the company took a considerable stake in UnitedHealth. The 5 million-share, $1.6 billion stake makes the massive health insurer the 18th-biggest position in Berkshire's portfolio. Buffett's company also trimmed its positions in Apple and Bank of America.

Shares of some of UnitedHealth’s peers got a bump in the wake of Berkshire’s investment in the healthcare giant, and they all look cheaper based on price relative to expected earnings.