I think you'd actually find the price has been creeping up for some time.... its just that you don't notice once you've ordered your car.
I'll bet VW increase the overall cost at least once every year, if not twice.
Definitely each MY sees an increase.
So KMP, thats at least 2 hikes since yours, lets assume 2 and if we look at the base price (because options tend not to move) we see 3.4% per annum.
TBH, that sounds about right.