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).
Lena has been climbing back after years of decline. All-time it's been given to 172,084 U.S. babies, the 397th most common name by sound today, peaking at 3,130 in 1917, with 1,845 in 2025.
By sound, Lena also includes the spellings Lina, Leena.
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).