How many people chose to keep their insurance with their existing job rather than to forego it in order to start a company? Economically speaking a 20-somethin

How many people chose to keep their insurance with their existing job rather than to forego it in order to start a company? Economically speaking a 20-something will have fewer responsibilities than say a 40-something with a family and children. So many startups have been funded by 20-somethings having the ability to couch surf and live off their parents health insurance -- likely because they're the only ones that can afford the risk.