SELECT  CASE WHEN age <= 4 THEN 'Under 4' WHEN age BETWEEN 5 and 9 THEN '5 - 9'
WHEN age BETWEEN 10 and 14 THEN '10 - 14' WHEN age BETWEEN 15 and 19 THEN '15 - 19'
WHEN age BETWEEN 20 and 24 THEN '20 - 24' WHEN age BETWEEN 25 and 29 THEN '25 - 29'
WHEN age BETWEEN 30 and 34 THEN '30 - 34' WHEN age BETWEEN 35 and 39 THEN '35 - 39'
WHEN age BETWEEN 40 and 44 THEN '40 - 44' WHEN age BETWEEN 45 and 49 THEN '45 - 49'
WHEN age BETWEEN 50 and 54 THEN '50 - 54' WHEN age BETWEEN 55 and 59 THEN '55 - 59'
WHEN age BETWEEN 60 and 64 THEN '60 - 64' WHEN age BETWEEN 65 and 69 THEN '65 - 69'
WHEN age >= 70 THEN 'Over 70' WHEN age IS NULL THEN 'Age Not Specified(null)'
END as age_range, count(distinct person_id) number_seeking_care,  CASE WHEN age <= 4 THEN 1
WHEN age BETWEEN 5 and 9 THEN 2  WHEN age BETWEEN 10 and 14 THEN 3  WHEN age BETWEEN 15 and 19 THEN 4
WHEN age BETWEEN 20 and 24 THEN 5  WHEN age BETWEEN 25 and 29 THEN 6
WHEN age BETWEEN 30 and 34 THEN 7  WHEN age BETWEEN 35 and 39 THEN 8 WHEN age BETWEEN 40 and 44 THEN 9
WHEN age BETWEEN 45 and 49 THEN 10 WHEN age BETWEEN 50 and 54 THEN 11 WHEN age BETWEEN 55 and 59 THEN 12
WHEN age BETWEEN 60 and 64 THEN 13 WHEN age BETWEEN 65 and 69 THEN 14 WHEN age >= 70 THEN 15
WHEN age IS NULL THEN 16 END as ordinal FROM (SELECT TIMESTAMPDIFF(YEAR, birthdate, CURDATE()) AS age,  pe.person_id FROM personevents pe
JOIN person p ON p.person_id = pe.person_id
JOIN facility f ON f.mflcode = pe.facility_mflcode ) as derived
GROUP BY age_range  ORDER BY  ordinal