condition mean min max ZT0-3 10.28325 10.28325 10.28325 ZT4-7 6.77745 6.77745 6.77745 ZT8-11 7.698435 7.698435 7.698435 ZT12-15 9.439025 9.439025 9.439025 ZT16-19 13.00345 13.00345 13.00345 ZT20-23 10.09395 10.09395 10.09395