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).
Evan has dropped sharply from its peak but is still widely used. All-time it's been given to 296,135 U.S. babies, the 287th most common name by sound today, peaking at 10,549 in 2007, with 2,496 in 2025.
By sound, Evan also includes the spellings Evin.