年齢を出生年(+万歳、国内年齢)に換算

const today = new Date();
const birthDate = new Date(row.birth);
let birthToAge =
  today.getFullYear() - birthDate.getFullYear() + 1;

const today = new Date();
const birthDate = new Date(row.birth);
let birthToAge =
  today.getFullYear() - birthDate.getFullYear();