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).
Sylvia
Sylvia has been climbing in recent years. All-time it's been given to 267,301 U.S. babies, the 655th most common name by sound today, peaking at 4,587 in 1957, with 1,199 in 2025.
By sound, Sylvia also includes the spellings Silvia.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).