condition mean min max ZT0-3 3.5560225 2.75998 4.352065 ZT4-7 1.8851175 1.8851175 1.8851175 ZT8-11 2.4937300000000002 2.4937300000000002 2.4937300000000002 ZT12-15 0 0 0 ZT16-19 1.83342 1.83342 1.83342 ZT20-23 2.252625 2.252625 2.252625