condition mean min max ZT0-3 4.44705 4.44705 4.44705 ZT4-7 2.609025 2.609025 2.609025 ZT8-11 1.47401 1.47401 1.47401 ZT12-15 2.36341 2.36341 2.36341 ZT16-19 7.10517 7.10517 7.10517 ZT20-23 4.65248 4.65248 4.65248