How many die from those who are hospitalized infected with coronavirus?

"Without vaccine you end up with that 2.5% chance of dying once you are hospitalized." [1]

1. Breakthrough Cases Rising, But Still Remain Uncommon
Whelan, Robbie; Hopkins, Jared S.  Wall Street Journal, Eastern edition; New York, N.Y. [New York, N.Y]. 18 Aug 2021: A.1.