condition mean min max ZT0-3 1.206315 0.813395 1.5992350000000002 ZT4-7 3.8504 3.8504 3.8504 ZT8-11 2.988975 2.988975 2.988975 ZT12-15 0 0 0 ZT16-19 2.153655 2.153655 2.153655 ZT20-23 1.51727 1.51727 1.51727