condition mean min max ZT0-3 3.399755 2.529895 4.269615 ZT4-7 2.667685 2.667685 2.667685 ZT8-11 3.621715 3.621715 3.621715 ZT12-15 0 0 0 ZT16-19 4.853205 4.853205 4.853205 ZT20-23 5.1567050000000005 5.1567050000000005 5.1567050000000005