Ganguly was captained the Indian team for more than four years, Dravid is just passed his 2nd year as captain, I think you can not make a judgement on this stats, I think there is still time left to make a judgement on this issue
For instance have a look at the world champions Steve Waugh was followed Ricky Pointing but the performance percentage of Pointing is higher compared to waugh irrespective for how long he captained aus.
