condition mean min max ZT0-3 27.836314 27.836314 27.836314 ZT4-7 22.367666 22.367666 22.367666 ZT8-11 13.637160000000002 13.637160000000002 13.637160000000002 ZT12-15 10.368238999999999 10.368238999999999 10.368238999999999 ZT16-19 11.360801 11.360801 11.360801 ZT20-23 11.3141915 11.3141915 11.3141915