condition mean min max ZT0-3 22.79855 21.7309 23.8662 ZT4-7 13.2506 13.2506 13.2506 ZT8-11 10.613205 10.613205 10.613205 ZT12-15 0 0 0 ZT16-19 14.2238 14.2238 14.2238 ZT20-23 19.05085 19.05085 19.05085