for 95 HSC mark, you could get lucky with a 92 or 93 raw, just depends on difficulty of exam etc etc
And the large gaps are legit. It gets harder and harder to go from a low 90s to a high 90s... If you're aiming for a HSC mark of >95 in any if not all of your subjects, you pretty much have to get a raw mark close to that desired HSC mark...