condition mean min max ZT0-3 21.830925 20.1027 23.559150000000002 ZT4-7 28.537399999999998 28.537399999999998 28.537399999999998 ZT8-11 19.627499999999998 19.627499999999998 19.627499999999998 ZT12-15 0 0 0 ZT16-19 24.768050000000002 24.768050000000002 24.768050000000002 ZT20-23 26.62005 26.62005 26.62005