condition mean min max ZT0-3 6.6017399999999995 6.6017399999999995 6.6017399999999995 ZT4-7 5.4707550000000005 5.4707550000000005 5.4707550000000005 ZT8-11 5.0704899999999995 5.0704899999999995 5.0704899999999995 ZT12-15 5.45182 5.45182 5.45182 ZT16-19 7.237285 7.237285 7.237285 ZT20-23 7.12193 7.12193 7.12193