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).
Danielle has been slowly declining from its former popularity. All-time it's been given to 396,874 U.S. babies, the 928th most common name by sound today, peaking at 17,977 in 1987, with 573 in 2025.
By sound, Danielle also includes the spellings Danyelle, Daniele, Dannielle, Danyel, Daniell, Danyell.