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).
Lois
Lois is now well below its former popularity. All-time it's been given to 335,594 U.S. babies, the 2,068th most common name by sound today, peaking at 10,587 in 1927, with 124 in 2025.
Lois has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).