Largest self-publishing companies in the United States in 2018 , by number of print books published is a bar plot. A categorical scale with Amazon’s CreateSpace/Independently Published on one end and Xlibris (Div. of Author Solutions) at the other can be seen on the y-axis, marked company. The x-axis plots Number of published titles on a linear scale with a minimum of 0 and a maximum of 1,500,000.