CASE
    WHEN dateDiff('day', pp.full_reg_datetime, now()) < 7 THEN 'A. < 1 week'
    WHEN dateDiff('day', pp.full_reg_datetime, now()) BETWEEN 7 AND 13 THEN 'B. ~ 1 week'
    WHEN dateDiff('day', pp.full_reg_datetime, now()) BETWEEN 14 AND 29 THEN 'C. 2-4 weeks'
    WHEN dateDiff('day', pp.full_reg_datetime, now()) BETWEEN 30 AND 59 THEN 'D. 1-2 months'
    WHEN dateDiff('day', pp.full_reg_datetime, now()) BETWEEN 60 AND 119 THEN 'E. 2-4 months'
    WHEN dateDiff('day', pp.full_reg_datetime, now()) BETWEEN 120 AND 239 THEN 'F. 4-8 months'
    WHEN dateDiff('day', pp.full_reg_datetime, now()) BETWEEN 240 AND 364 THEN 'G. 8-12 months'
    WHEN dateDiff('day', pp.full_reg_datetime, now()) BETWEEN 365 AND 729 THEN 'H. 1-2 years'
    ELSE 'I. > 2 years'
END AS weeks_group