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).
Stephan
Stephan has stayed fairly steady in American naming for generations. All-time it's been given to 57,969 U.S. babies, the 1,250th most common name by sound today, peaking at 1,609 in 1991, with 351 in 2025.
By sound, Stephan also includes the spellings Stefan, Stephon.
Rising