condition mean min max ZT0-3 15.572725000000002 14.36285 16.782600000000002 ZT4-7 14.80695 14.80695 14.80695 ZT8-11 20.471049999999998 20.471049999999998 20.471049999999998 ZT12-15 0 0 0 ZT16-19 20.1231 20.1231 20.1231 ZT20-23 17.6446 17.6446 17.6446