condition mean min max ZT0-3 7.073487500000001 6.65793 7.489045000000001 ZT4-7 7.690595 7.690595 7.690595 ZT8-11 13.39065 13.39065 13.39065 ZT12-15 0 0 0 ZT16-19 19.718249999999998 19.718249999999998 19.718249999999998 ZT20-23 11.955100000000002 11.955100000000002 11.955100000000002