Source: Author's calculations from SNL with exchange enrollment from ASPE and population from Census. Post values are averages from 2014Q1 and 2014Q2, weighted by average monthly enrollment. Pre values are an estimate of what the post value would have been absent the implementation of the ACA. They are obtained by estimating a seasonally-adjusted trend regression for each series from 2008Q1 to 2014Q2, omitting 2013Q4 and allowing for a separate intercept for 2014. The pre value reflects the post value minus the 2014 intercept. See text for more details.