Infact, I remember from the 1997 elections that NS was infact paying tax, though the amount was peanuts compared to what he was making.
Well NS was paying taxes till 1999, though as you mentioned peanuts compared to his income, thru cooked books he showed losses in the factories/industries he was in possession of.
Ehstesab, how did you look up Miandad's tax records? Miandad was considered to be one of Pakistan's richest at one time.
I didn't get this info from this website, this is from my memory of articles published in newspapers back in 90s. I don't think he was "richest" when he paid that much income tax, but probably he was making good money those days so he paid taxes accordingly unlike Nawaz/Bibi who barely paid taxes.