condition mean min max ZT0-3 2.90191 2.3638399999999997 3.72561 ZT4-7 2.986205 2.986205 2.986205 ZT8-11 2.7893499999999998 2.7893499999999998 2.7893499999999998 ZT12-15 4.098027500000001 3.289785 4.90627 ZT16-19 2.908525 2.908525 2.908525 ZT20-23 3.8240749999999997 3.8240749999999997 3.8240749999999997