condition mean min max ZT0-3 2.085706 2.041372 2.13004 ZT4-7 5.11267 5.11267 5.11267 ZT8-11 12.697199999999999 12.697199999999999 12.697199999999999 ZT12-15 0 0 0 ZT16-19 4.71138 4.71138 4.71138 ZT20-23 2.0228 2.0228 2.0228