When it comes to the market’s fastest-growing industries, you’d have a hard time topping legal marijuana. According to the latest report from Marijuana Business Daily entitled “Marijuana Business Factbook 2017,” U.S. legal weed sales are expected to grow by approximately 30% in 2017, 45% the following year, and explode higher by roughly 300% between 2016 and 2021. This would push the U.S. legal cannabis market to around $17 billion by 2021.