Although Netflix (NFLX -0.63%) had enormous subscribership growth in 2011, its costs also exploded that year, leading to the company's least profitable year yet in 2012. How should investors read this to know where the company is headed in 2013? In the video below, Fool consumer goods analyst Blake Bos gives investors the most important ratios to follow to know whether some of Netflix's most recent headline-making endeavors are truly paying off for shareholders.