The original J.P. Morgan paper where this appeared isn't linked but they do say:
"Schulz states that the chart excludes the Postmaster General, Navy, War, Health, Education & Welfare, Veterans Affairs, and Homeland Security positions."
There's no question his cabinet was light on private sector experience but Hillary, Salazar, Vilsack, Duncan, Chu, Emaunel and Orszag each had some.
I'm sure there's some reasoning behind the chart but I don't see how they could possibly get to less than 10%.