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).
Cecelia
Cecelia is now well below its former popularity. All-time it's been given to 60,530 U.S. babies, the 954th most common name by sound today, peaking at 935 in 1918, with 569 in 2025.
Cecelia has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).