condition mean min max ZT0-3 17.649725 17.3331 17.96635 ZT4-7 15.1214 15.1214 15.1214 ZT8-11 23.7619 23.7619 23.7619 ZT12-15 0 0 0 ZT16-19 21.2362 21.2362 21.2362 ZT20-23 13.2863 13.2863 13.2863