condition mean min max ZT0-3 14.73075 14.73075 14.73075 ZT4-7 12.4891 12.4891 12.4891 ZT8-11 12.06775 12.06775 12.06775 ZT12-15 13.01215 13.01215 13.01215 ZT16-19 16.1491 16.1491 16.1491 ZT20-23 14.3463 14.3463 14.3463