E-book sales grew exponentially in 2011, far exceeding expectations. In the US, e-book sales increased 277% from 2009 to 2010, and growth continued strongly in 2011. Publishers reported substantial increases in e-book sales in the first few months of 2011 compared to the same period in 2010. The gap between the US and UK e-book markets was shrinking as global e-book sales rose rapidly. Self-publishing was facilitated by e-books as it provided higher profit margins than traditional publishing and allowed authors to bypass the industry's infrastructure. E-books stimulated new models of publishing and reading as their adoption varied across demographics and genres.