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).
Rachel has been slowly declining from its former popularity. All-time it's been given to 675,170 U.S. babies, the 545th most common name by sound today, peaking at 19,836 in 1991, with 1,287 in 2025.
By sound, Rachel also includes the spellings Rachael, Racheal, Rachell, Raechel.