I calculated the higher education enrollment rates at state level using ACS from 2001 to 2012. I know that since 2006, the ACS captures population living in group quarters. Given the topic that I am analysing (enrollment in higher education of multiple population groups), how can I make appropiate comparison between ACS pre and post 2006? Should I work only with information from individuals living in households, i.e., those with gq equal 1 and 2?
Also, how appropiate is to make comparisons between ACS 2001-2004 and ACS from 2005 and beyond given the substantial differences in sample size?
Thank you for your help.