condition mean min max ZT0-3 1.9089075 1.46706 2.350755 ZT4-7 8.1115 8.1115 8.1115 ZT8-11 33.1389 33.1389 33.1389 ZT12-15 0 0 0 ZT16-19 17.678350000000002 17.678350000000002 17.678350000000002 ZT20-23 6.248275 6.248275 6.248275