They with a singular antecedent goes back to the
Middle English of the 14th century
[35][36] (slightly younger than
they with a plural antecedent, which was borrowed from
Old Norse in the 13th century),
[37] and has remained in use for centuries in spite of its proscription by traditional grammarians beginning in the mid 18th century.
[38][39]
Informal spoken English exhibits universal use of the singular
they. An examination by Jürgen Gerner of the
British National Corpus published in 1998 found that British speakers, regardless of social status, age, sex, or region, used the singular
they more often than the gender-neutral
he or other options.
[40]