condition mean min max ZT0-3 29.149700000000003 26.68775 31.61165 ZT4-7 13.286200000000001 13.286200000000001 13.286200000000001 ZT8-11 12.19155 12.19155 12.19155 ZT12-15 0 0 0 ZT16-19 21.7036 21.7036 21.7036 ZT20-23 21.46425 21.46425 21.46425