condition mean min max ZT0-3 2.3450775000000004 2.1352700000000002 2.554885 ZT4-7 1.7069450000000002 1.7069450000000002 1.7069450000000002 ZT8-11 2.7957650000000003 2.7957650000000003 2.7957650000000003 ZT12-15 0 0 0 ZT16-19 5.421245000000001 5.421245000000001 5.421245000000001 ZT20-23 2.913415 2.913415 2.913415