Pretty predictable. Young/first time new car buyers and older/retirees. Inexpensive small car. People in between tend to have families and higher incomes so need and can afford larger and more expensive vehicles.
Yes, it's the right car for retired folks too! Hoping for ten years/150,000 miles of fun and reliable motoring from my new Yaris.
Since mine is to be a 2019 it transcends the Scion 1A, Yaris iA labels, not to mention Mazda.