condition mean min max ZT0-3 11.7381 11.7381 11.7381 ZT4-7 5.93041 5.93041 5.93041 ZT8-11 6.13345 6.13345 6.13345 ZT12-15 5.347195 5.347195 5.347195 ZT16-19 11.4871 11.4871 11.4871 ZT20-23 12.149 12.149 12.149