condition mean min max ZT0-3 469.1861666666667 460.83 485.706 ZT4-7 439.0815 439.0815 439.0815 ZT8-11 384.8155 384.8155 384.8155 ZT12-15 262.61325 253.2045 272.022 ZT16-19 243.3765 243.3765 243.3765 ZT20-23 302.6 302.6 302.6