According to a Forrester Research report, online retail sales in the US are forecast to grow substantially from 2011 to 2016, with 15% more buyers shopping online and spending up to 44% more on average. The number of online buyers is expected to increase from 167 million in 2011 to 196 million in 2016, while average spending per buyer may rise from $1,000 to $1,440. Mobile e-commerce sales are also growing rapidly, projected to increase from $3 billion in 2010 to $31 billion in 2016. Magento, Oscommerce, and Open Cart are three popular content management systems for e-commerce websites, with each having certain distinctive features.