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).
Daphne has been climbing in recent years. All-time it's been given to 47,712 U.S. babies, the 454th most common name by sound today, peaking at 1,977 in 2025, with 1,977 in 2025.
By sound, Daphne also includes the spellings Dafne.
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).