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).
Case
Case has stayed fairly steady in American naming for generations. All-time it's been given to 17,994 U.S. babies, the 781st most common name by sound today, peaking at 1,249 in 2018, with 772 in 2025.
By sound, Case also includes the spellings Kase, Kace.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).