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).
Boston
Boston climbed for decades and has been a steadily popular name ever since. All-time it's been given to 11,944 U.S. babies, the 1,062nd most common name by sound today, peaking at 562 in 2014, with 505 in 2025.
Boston has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).