You win Henlee, Obama ain't cooking the books.If you look at the definition these border arrests are arrests where they are brought in and processed and not simply just turned away. So if out in the desert they catch a bunch of people crossing illegally that would count as a border arrest. If they caught people at the crossing with fake people then that would count also if they arrested them. If Pablo walks up and asks if he can come in and they say no and he turns around and walks home. that doesn't count. So at minimum you have made the strong case that Obama has strengthened our protection at the border. This by the way is a good thing. The Cato report tracked this for the years Bush was in office so I am not buying that Obama changed the rules for himself.
You can ignore that however and focus then on arrests made in the Interior of the country and they are still double of what Bush did or even more.
Straight from the glossary of the report you provided.
Border Removal: An individual removed by ICE who is apprehended while attempting to illicitly enter the United States at or between the ports of entry by a CBP officer or agent. These individuals are also referred to as recent border crossers.