condition mean min max ZT0-3 6.789795 6.64143 6.93816 ZT4-7 6.656365 6.656365 6.656365 ZT8-11 4.302495 4.302495 4.302495 ZT12-15 0 0 0 ZT16-19 7.292304999999999 7.292304999999999 7.292304999999999 ZT20-23 8.86853 8.86853 8.86853