Haven't been checking this but didn't expect Ps4's 2018 to be 1 million higher than Switches 2019.
That's a bit surprising, but I think it'll be pretty close in the end. Given that Switch is over a million ahead of where it was last year, it probably won't lose that lead on its previous year, and that makes it on track to sell 17,565,922 at the moment for 2019. Given that Nintendo's sales are holiday heavy, that lead will probably increase a bit in the end, so Switch will inevitably close much of that gap with PS4's 2018, and might even surpass it in the end. Clearly barring a disaster Switch's 2019 will beat its 2018, so the Switch 2019 to PS4 2018 race will probably be more interesting to watch.