condition mean min max ZT0-3 76.105997 76.105997 76.105997 ZT4-7 38.5852385 38.5852385 38.5852385 ZT8-11 28.8087305 28.8087305 28.8087305 ZT12-15 25.947854 25.947854 25.947854 ZT16-19 23.528278999999998 23.528278999999998 23.528278999999998 ZT20-23 19.546132 19.546132 19.546132