condition mean min max ZT0-3 20.8955 20.8955 20.8955 ZT4-7 12.6321 12.6321 12.6321 ZT8-11 14.1338 14.1338 14.1338 ZT12-15 18.5158 18.5158 18.5158 ZT16-19 27.000700000000002 27.000700000000002 27.000700000000002 ZT20-23 24.42965 24.42965 24.42965