condition mean min max ZT0-3 10.486221 10.486221 10.486221 ZT4-7 9.0395065 9.0395065 9.0395065 ZT8-11 10.451061500000002 10.451061500000002 10.451061500000002 ZT12-15 9.642095000000001 9.642095000000001 9.642095000000001 ZT16-19 9.881513 9.881513 9.881513 ZT20-23 9.827626500000001 9.827626500000001 9.827626500000001