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).
Amelia has climbed over the years and is holding near its high. All-time it's been given to 350,535 U.S. babies, the 3rd most common name by sound today, peaking at 17,903 in 2021, with 17,387 in 2025.
By sound, Amelia also includes the spellings Emilia.