condition mean min max ZT0-3 1.435485 1.39566 1.47531 ZT4-7 1.89112 1.89112 1.89112 ZT8-11 2.37975 2.37975 2.37975 ZT12-15 0 0 0 ZT16-19 2.85375 2.85375 2.85375 ZT20-23 2.4913600000000002 2.4913600000000002 2.4913600000000002