How to read the band →
Solid line = floor (spellings that unambiguously belong to the group). Shaded band up to the dashed edge = ceiling (the most it could reach if every ambiguous spelling counted here).
Johan
Johan has stayed fairly steady in American naming for generations. All-time it's been given to 20,307 U.S. babies, the 945th most common name by sound today, peaking at 827 in 2016, with 601 in 2025.
By sound, Johan also includes the spellings Johann.
Rising