condition mean min max ZT0-3 22.08425 19.4063 24.1193 ZT4-7 17.1214 17.1214 17.1214 ZT8-11 16.5321 16.5321 16.5321 ZT12-15 29.548775 28.319699999999997 30.77785 ZT16-19 23.19045 23.19045 23.19045 ZT20-23 25.46875 25.46875 25.46875