condition mean min max ZT0-3 26.189332 26.189332 26.189332 ZT4-7 32.397287500000004 32.397287500000004 32.397287500000004 ZT8-11 30.647318999999996 30.647318999999996 30.647318999999996 ZT12-15 31.623689 31.623689 31.623689 ZT16-19 23.789979000000002 23.789979000000002 23.789979000000002 ZT20-23 24.3671685 24.3671685 24.3671685