condition mean min max ZT0-3 8.071197 8.071197 8.071197 ZT4-7 11.146908499999999 11.146908499999999 11.146908499999999 ZT8-11 10.069719500000001 10.069719500000001 10.069719500000001 ZT12-15 10.257698000000001 10.257698000000001 10.257698000000001 ZT16-19 9.7418405 9.7418405 9.7418405 ZT20-23 11.282638 11.282638 11.282638