condition mean min max ZT0-3 5.1 5.1 5.1 ZT4-7 9.3 9.3 9.3 ZT8-11 7.2 7.2 7.2 ZT12-15 7.050000000000001 7.050000000000001 7.050000000000001 ZT16-19 4.1 4.1 4.1 ZT20-23 4.8 4.8 4.8