condition mean min max ZT0-3 2.45416 2.45416 2.45416 ZT4-7 3.1990100000000004 3.1990100000000004 3.1990100000000004 ZT8-11 2.97204 2.97204 2.97204 ZT12-15 2.772335 2.772335 2.772335 ZT16-19 2.13504 2.13504 2.13504 ZT20-23 2.40198 2.40198 2.40198