condition mean min max ZT0-3 14.639725 13.1114 16.16805 ZT4-7 8.22054 8.22054 8.22054 ZT8-11 6.88538 6.88538 6.88538 ZT12-15 0 0 0 ZT16-19 14.8088 14.8088 14.8088 ZT20-23 14.277650000000001 14.277650000000001 14.277650000000001