Marginal Tax Rates under Obamacare

Back in 2009, I pointed out in a NY Times column that President Obama's healthcare reform would involve substantial increases in implicit marginal tax rates.  I am delighted that Casey Mulligan is now giving the issue some serious attention in two new NBER working papers (here and here).  He reports:

This paper calculates the ACA’s impact on the average reward to working among nonelderly household heads and spouses. The law increases marginal tax rates by an average of five percentage points (of employee compensation), on top of the marginal tax rates that were already present before the it went into effect....Measured in percentage points, the Affordable Care Act will, by 2015, add about twelve times more to average marginal labor income tax rates nationwide than the Massachusetts health reform added to average rates in Massachusetts following its 2006 statewide health reform.