condition mean min max ZT0-3 4.618625 4.618625 4.618625 ZT4-7 3.5100749999999996 3.5100749999999996 3.5100749999999996 ZT8-11 3.539315 3.539315 3.539315 ZT12-15 3.4593249999999998 3.4593249999999998 3.4593249999999998 ZT16-19 4.6763200000000005 4.6763200000000005 4.6763200000000005 ZT20-23 4.6021 4.6021 4.6021