The parliamentary budget officer pointed out that yes, it is a negative impact, but the figures in the budget go out to the second year of implementation, 2017-18. The parliamentary budget officer finds a negative impact on GDP of $30 million. That would have been a rounding error in the figures that are presented here.
When combined with the impact of other measures you just don't see it. The impact of the measure was certainly taken into account but it's small in terms of the overall picture.