condition mean min max ZT0-3 1.8453525 1.347585 2.34312 ZT4-7 1.9454449999999999 1.9454449999999999 1.9454449999999999 ZT8-11 1.308505 1.308505 1.308505 ZT12-15 0 0 0 ZT16-19 3.62466 3.62466 3.62466 ZT20-23 2.9357550000000003 2.9357550000000003 2.9357550000000003