condition mean min max ZT0-3 3.4783399999999998 3.4783399999999998 3.4783399999999998 ZT4-7 9.500019 9.500019 9.500019 ZT8-11 3.303215 3.303215 3.303215 ZT12-15 3.8785600000000002 3.8785600000000002 3.8785600000000002 ZT16-19 5.316643333333333 5.316643333333333 5.316643333333333 ZT20-23 3.85628 3.85628 3.85628