How does the radius of a positive and negative ion compare to a neutral atom?

A neutral atom contains equal amount of proton and electron.

A negative ion contains extra electrons hence there is additional outer shell so it is expected that the radius is bigger than that of a neutral atom.

While a positive ion contains less electron so there is less outer shell so the radius is smaller than that of a neutral atom.

Arranging the radius in increasing order:

positive ion, neutral atom, negative ion

a reflection across the x axis and a 90 degree rotation left and right.