condition mean min max ZT0-3 6.8119250000000005 6.1863850000000005 7.4374649999999995 ZT4-7 3.4524800000000004 3.4524800000000004 3.4524800000000004 ZT8-11 16.498199999999997 16.498199999999997 16.498199999999997 ZT12-15 0 0 0 ZT16-19 16.2096 16.2096 16.2096 ZT20-23 11.529195 11.529195 11.529195