condition mean min max ZT0-3 6.984783333333333 5.30247 8.588555 ZT4-7 5.66353 5.66353 5.66353 ZT8-11 6.431435 6.431435 6.431435 ZT12-15 9.102382500000001 8.15874 10.046025 ZT16-19 9.48391 9.48391 9.48391 ZT20-23 8.74032 8.74032 8.74032