Don't forget only a 'selected group' of DBS students attended IB, the marks of which, of course would be higher than the average if all of them attended.
Yes...that's true... I think the real potential of SIS will be more truly reflected a few years later when the effect of 'exodus' to GSIS and CIS in the past is minimized .....
There was 'exodus' in the past because SIS didnot provide higher secondary education by then