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).
Noah has been climbing in recent years. All-time it's been given to 548,871 U.S. babies, the 1st most common name by sound today, peaking at 22,447 in 2024, with 22,399 in 2025.
By sound, Noah also includes the spellings Noa.