Again my reading (with no actual knowledge of the EU policy) is that the 2021 figure is the estimated escalating cost. Ie: they're a few g/km over the current 120 g/km standard, and unless they get there emissions under control, they'll be seriously over the 90g/km std due to take effect by 2021.
Perhaps some of our European members can provide more color on EU emissions regs.
Paging @avoigt @hobbes @lklundin
Cheers!
Thanks for mentioning me - but I don´t know much about that, sorry. BTW, you´re forgetting quite a few other European members!