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).
Ann is now well below its former popularity. All-time it's been given to 797,579 U.S. babies, the 839th most common name by sound today, peaking at 14,686 in 1959, with 697 in 2025.
By sound, Ann also includes the spellings Anne.
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).