condition mean min max ZT0-3 11.247358333333334 5.894175 14.5943 ZT4-7 7.488104999999999 7.488104999999999 7.488104999999999 ZT8-11 5.10008 5.10008 5.10008 ZT12-15 6.6276075 5.412635 7.84258 ZT16-19 7.96171 7.96171 7.96171 ZT20-23 11.005015 11.005015 11.005015