Ask HN: Data on What Fraction of Startups are Profitable?

Pretty much what it says in the title. Does anyone know where to find data on what fraction of (tech) startups are profitable? And just to be clear, by profitable I don't mean profitable for the investors or owners, but that the business makes more than it costs to run.

I'm asking specifically because entrepreneurship is often vaunted as an excellent career path for smart, ambitious people, but there is a lack of transparency about how many people succeed and how much of that success is due to building a real business vs getting acquired without real profit.