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).
Maximilian
Maximilian climbed for decades and has been a steadily popular name ever since. All-time it's been given to 18,940 U.S. babies, the 1,042nd most common name by sound today, peaking at 717 in 2016, with 497 in 2025.
Maximilian has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).