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).
Andy
Andy has stayed fairly steady in American naming for generations. All-time it's been given to 109,380 U.S. babies, the 521st most common name by sound today, peaking at 2,263 in 2005, with 1,472 in 2025.
By sound, Andy also includes the spellings Andi, Andie.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).