At this point, we have now been collecting the GST for 16 years; as for income tax, the temporary tax goes back 90 years to 1917.
I think it's fair to say after all those years, whether you're talking 16 or 90 years, that we have developed the systems and capacity and expertise to collect both taxes quite efficiently right now. So it would be difficult I think for anybody to say which one is cheaper to administer in terms of the incremental dollar.
Perhaps the Department of Finance has done studies to that effect, but I'm not aware of any.