condition mean min max ZT0-3 30.333619 30.333619 30.333619 ZT4-7 27.055593000000002 27.055593000000002 27.055593000000002 ZT8-11 21.764645 21.764645 21.764645 ZT12-15 21.7476675 21.7476675 21.7476675 ZT16-19 20.2301615 20.2301615 20.2301615 ZT20-23 17.5923455 17.5923455 17.5923455