condition mean min max ZT0-3 2.044365 1.7108949999999998 2.377835 ZT4-7 2.7301 2.7301 2.7301 ZT8-11 1.96711 1.96711 1.96711 ZT12-15 0 0 0 ZT16-19 2.61601 2.61601 2.61601 ZT20-23 2.0661050000000003 2.0661050000000003 2.0661050000000003