Relatively it isn' t a price increase of 20%. If we are going to talk in percentages anyway . It has an increase of 100% against the iPad Air 2 in storage: 16gb vs 32gb.
And about that: iPad 2 32gb, iPad 3 32gb , iPad 4 32gb and iPad air 1 32 gb were released at 599us.For the 64gb they charged 699
So with the air 2 you got a break for 64gb at 599. Otherwise it has always been 599 for 32gb.
So the 2014 decrease of 15% should not be normal accordingly to your standards.
And now they corrected it to normal..
The price of those components continually go down as time goes by. They are still charging the same price as 6 years ago. Has technology not improved in 6 years? Otherwise, my standards stand.