How to read the band →
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).
Cindy
Cindy is now well below its former popularity. All-time it's been given to 269,329 U.S. babies, the 2,125th most common name by sound today, peaking at 20,912 in 1957, with 100 in 2025.
By sound, Cindy also includes the spellings Cindi, Cyndi.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).