condition mean min max ZT0-3 27.68445 27.68445 27.68445 ZT4-7 20.27345 20.27345 20.27345 ZT8-11 21.30455 21.30455 21.30455 ZT12-15 23.270850000000003 23.270850000000003 23.270850000000003 ZT16-19 37.185050000000004 37.185050000000004 37.185050000000004 ZT20-23 30.68155 30.68155 30.68155