Select Users Age in MySQL

SELECT count(id) AS toplam,YEAR(tarih_dogum) AS YIL FROM uyeler GROUP BY YEAR(tarih_dogum)

Advertising agencies wants to user profile for advertisements. I need my users age. I found a little solution. I write this SQL statement for select which year my users born and group them.

SELECT count(id) AS total,YEAR(birthday) AS birth_year FROM users GROUP BY YEAR(birthday);
After i copied this results to Excel. I calculate age groups like “18-24 years old” in Excel and send my offer to agencies.