I'm confused by your claim that pay will be reduced in 2017. Clearly your 2017 figure is less than your 2016 figure? Also you'll note your 2018 figure is less than 2016.
Seemingly when you posted the figures above, you did at that point agree that there's a difference between the cost over three years versus cost in year three, since you were trying to get the costs over three years to add up to around 2k.
PER seem to have made an error when describing a 2k over 3 year deal for 300,000 workers as "The agreement has additional costs of €566 million over a 3 year period.."
To explain the PER figure, so far you've claimed it's due to it being net of tax, next because there's some pay cut being implemented in 2017, and now it being because pay rises via reduction in PRD are not pay rises. Isn't the simplest explanation that the description of the cost by PER is incorrect?