condition mean min max ZT0-3 19.26955 17.97665 20.56245 ZT4-7 15.611699999999999 15.611699999999999 15.611699999999999 ZT8-11 26.53215 26.53215 26.53215 ZT12-15 0 0 0 ZT16-19 32.334649999999996 32.334649999999996 32.334649999999996 ZT20-23 31.662800000000004 31.662800000000004 31.662800000000004