Counterfactual
The Parallel Lives of Jair and Jonas
In 170 boys, Jair found its level. 50 years earlier, Jonas occupied that same statistical address.
1971–2025
Jair
Peak year
2003
Peak births
480
Latest count
170
Status
Stable
Peak generation
Gen Z
1880–2025
Jonas
Peak year
2008
Peak births
1,256
Latest count
476
Status
Declining
Peak generation
Gen Z
Jair and Jonas peaked in the same cultural weather — the Gen Z naming world. They are not replacements; they are siblings separated by 50 years, occupying the same statistical address at different addresses in time.