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).
Naya has held a fairly steady level of use. All-time it's been given to 18,034 U.S. babies, the 1,016th most common name by sound today, peaking at 1,116 in 2001, with 478 in 2025.
By sound, Naya also includes the spellings Nya, Nyah. Spellings sometimes heard the same way: Niya.
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).