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).
Susan
Susan is now well below its former popularity. All-time it's been given to 1,135,103 U.S. babies, the 1,647th most common name by sound today, peaking at 47,967 in 1955, with 222 in 2025.
By sound, Susan also includes the spellings Suzan.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).