condition mean min max ZT0-3 9.7225975 8.232145 11.21305 ZT4-7 8.17457 8.17457 8.17457 ZT8-11 3.606065 3.606065 3.606065 ZT12-15 0 0 0 ZT16-19 5.75721 5.75721 5.75721 ZT20-23 9.036380000000001 9.036380000000001 9.036380000000001