22% of UK's population is unvaccinated.

UK's total population number is 67 million.

So 0.22 * 67,000,000 = 14.7 Million people unvaccinated

And 0.78 * 67,000,000 = 52.3 Million people vaccinated

If the vaccine were just saline and had zero effectiveness, you'd expect the same results whether you were vaccinated or not.

Which would result in the green bars all being at 22%.

When the green bars are below 22%, that means the unvaccinated are doing better than the vaccinated.