condition mean min max ZT0-3 20.583366666666667 17.573 22.6038 ZT4-7 16.33365 16.33365 16.33365 ZT8-11 18.76065 18.76065 18.76065 ZT12-15 23.3447 22.9041 23.7853 ZT16-19 18.67155 18.67155 18.67155 ZT20-23 24.8343 24.8343 24.8343