age calculation in ruby

human.rb

require 'time'

class Human
  attr_reader :birth_date
  
  def initialize(birth_date)
    @birth_date = birth_date
  end
  
  
  def age
    now = Time.now.utc.to_date
    correction = now.strftime('%m%d') < birth_date.strftime('%m%d') ? 1 : 0
    now.year - birth_date.year - correction
  end
end