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).
Bridget was more common in the past and has since settled at a lower, steady level. All-time it's been given to 138,718 U.S. babies, the 1,016th most common name by sound today, peaking at 3,962 in 1973, with 544 in 2025.
By sound, Bridget also includes the spellings Bridgette, Bridgett, Brigitte.