condition mean min max ZT0-3 10.147091666666666 6.953175 12.265450000000001 ZT4-7 6.695195 6.695195 6.695195 ZT8-11 6.28881 6.28881 6.28881 ZT12-15 8.429870000000001 7.3749 9.48484 ZT16-19 10.47462 10.47462 10.47462 ZT20-23 12.0205 12.0205 12.0205