condition mean min max ZT0-3 1.8536025 1.44834 2.258865 ZT4-7 3.49283 3.49283 3.49283 ZT8-11 0.3962425 0.3962425 0.3962425 ZT12-15 0 0 0 ZT16-19 0.510431 0.510431 0.510431 ZT20-23 3.05767 3.05767 3.05767