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).
Angela was more common in the past and has since settled at a lower, steady level. All-time it's been given to 678,973 U.S. babies, the 624th most common name by sound today, peaking at 26,142 in 1971, with 776 in 2025.
By sound, Angela also includes the spellings Angella.