condition mean min max ZT0-3 2.37462575 1.6428565000000002 3.106395 ZT4-7 0.706105 0.706105 0.706105 ZT8-11 1.21503 1.21503 1.21503 ZT12-15 0 0 0 ZT16-19 3.993185 3.993185 3.993185 ZT20-23 5.66848 5.66848 5.66848