condition mean min max ZT0-3 851.794723 851.794723 851.794723 ZT4-7 1370.6856845 1370.6856845 1370.6856845 ZT8-11 1360.39706 1360.39706 1360.39706 ZT12-15 1237.095657 1237.095657 1237.095657 ZT16-19 1004.6293435 1004.6293435 1004.6293435 ZT20-23 940.387108 940.387108 940.387108