condition mean min max ZT0-3 6.96206 6.693809999999999 7.176125000000001 ZT4-7 5.01229 5.01229 5.01229 ZT8-11 6.5797 6.5797 6.5797 ZT12-15 10.02951 9.481864999999999 10.577155000000001 ZT16-19 9.46613 9.46613 9.46613 ZT20-23 8.55022 8.55022 8.55022