These are the rules for the Decades Challenge by CuteCoffeeGal that SeeJenGame has been following in her Decades Challenge for the Sims 4 on YouTube.
These are the original rules for the Decades Challenge by ZombieCleo. CuteCoffeeGal based her rules from these making them more historically accurate.
These are the rules for the Decades Challenge by Kakerus_Naruse. They have taken the original rules by ZombieCleo and made them more historically accurate. CuteCoffeeGal based her rules off the original and these ones.