condition mean min max ZT0-3 8.233212 8.233212 8.233212 ZT4-7 9.7979795 9.7979795 9.7979795 ZT8-11 9.2837305 9.2837305 9.2837305 ZT12-15 9.306987 9.306987 9.306987 ZT16-19 9.7512675 9.7512675 9.7512675 ZT20-23 9.5809245 9.5809245 9.5809245