condition mean min max ZT0-3 1.6977574999999998 1.507795 1.8877199999999998 ZT4-7 1.1071355 1.1071355 1.1071355 ZT8-11 1.747195 1.747195 1.747195 ZT12-15 0 0 0 ZT16-19 3.173005 3.173005 3.173005 ZT20-23 2.6299200000000003 2.6299200000000003 2.6299200000000003