condition mean min max ZT0-3 689.456852 689.456852 689.456852 ZT4-7 401.915574 401.915574 401.915574 ZT8-11 318.837187 318.837187 318.837187 ZT12-15 368.7862715 368.7862715 368.7862715 ZT16-19 347.09824100000003 347.09824100000003 347.09824100000003 ZT20-23 340.012779 340.012779 340.012779