condition mean min max ZT0-3 3.4483275000000004 3.373555 3.5231000000000003 ZT4-7 3.31073 3.31073 3.31073 ZT8-11 2.388345 2.388345 2.388345 ZT12-15 0 0 0 ZT16-19 3.36381 3.36381 3.36381 ZT20-23 5.171005 5.171005 5.171005