condition mean min max ZT0-3 5.3 5.3 5.3 ZT4-7 3.4 3.4 3.4 ZT8-11 4.949999999999999 4.949999999999999 4.949999999999999 ZT12-15 16.25 16.25 16.25 ZT16-19 15.2 15.2 15.2 ZT20-23 7.1 7.1 7.1