condition mean min max ZT0-3 83.937071 83.937071 83.937071 ZT4-7 766.04322 766.04322 766.04322 ZT8-11 1102.693774 1102.693774 1102.693774 ZT12-15 602.947804 602.947804 602.947804 ZT16-19 158.872333 158.872333 158.872333 ZT20-23 142.771049 142.771049 142.771049