[expatpat]

...when the British pulled out their systems quickly were abandon[ed]

Not really true. Look at the three biggest: India, Canada, Australia.

[buwaya]

On ex-colonies -
Pakistan, Bangladesh and Nigeria are bigger than Canada and Australia - population-wise anyway.

[Harmless Teddy Bear]

I said with a "few notable exceptions". India yes, in a fashion, but in the case of Canada and Australia you could argue that they were settlements rather then colonies.