condition mean min max ZT0-3 12.6052475 10.497545 14.71295 ZT4-7 6.20166 6.20166 6.20166 ZT8-11 4.090125 4.090125 4.090125 ZT12-15 0 0 0 ZT16-19 2.80464 2.80464 2.80464 ZT20-23 2.9044749999999997 2.9044749999999997 2.9044749999999997