This document is about an analysis of the funding mechanism of employer-sponsored health benefit plans that filed a Form 5500 Annual Return/Report of Employee Benefit Plans. It compares fully insured, self-insured, and mixed-funded health plans for reporting periods that ended in 2019 and presents historical series for 2010 through 2019. The report separates plans with at least 100 participants ("large plans") from plans with fewer than 100 participants ("small plans"), and provides insights on trends, plan characteristics, and financial metrics related to funding mechanisms.