Listen now (26 mins) | Listen Now While coverage under the Affordable Care Act (ACA), Medicare and Medicaid enjoy, deservedly, a great deal of discussion and debate, employer-sponsored insurance (ESI) insures approximately 55% of the non-Medicare eligible population, or approximately 152 million Americans. (Medicaid insures 19.5% of the population and Medicare 16%). Larger employers, or those with over 500 employees, are moreover (82%) self insured, 26% of smaller employers are as well. What we know about ESI and what further we can learn is therefore of substantial importance.