Last year, $3.4 billion of legal marijuana was sold in the United States, according to Marijuana Business Daily’s Marijuana Business Factbook . Legal in Alaska, Colorado, Oregon, Washington, and the District of Columbia, that's a lot of green for just a few states. The best way to give that figure some proper perspective is by comparing it with some of the country's best loved brands. Oreo is a good example. It had just over $700 million sales between April 2014 and April 2015 and weed sales were five times higher. In 2016, legal marijuana sales could be as high as $4.3 billion.