2019 is the last year of the 2010s; 2026 is in the 2020s. Obvious answer DOPE!
A period of ten years.

If you want to stick with defining within 10s or 20s your just an idiot. 7 years ago it doesn't count? So if I posted it next year and it happened in 2020 then it counted?

The lengths you scumbags will go to trying to justify your crimes is admirable.
Here, this easier for you?
