condition mean min max ZT0-3 4.7781666666666665 3.121045 5.649979999999999 ZT4-7 4.13788 4.13788 4.13788 ZT8-11 3.0648400000000002 3.0648400000000002 3.0648400000000002 ZT12-15 3.801025 3.11756 4.48449 ZT16-19 3.212415 3.212415 3.212415 ZT20-23 6.68053 6.68053 6.68053