condition mean min max ZT0-3 10.411100000000001 10.411100000000001 10.411100000000001 ZT4-7 8.49586 8.49586 8.49586 ZT8-11 7.5192499999999995 7.5192499999999995 7.5192499999999995 ZT12-15 9.49054 9.49054 9.49054 ZT16-19 12.90285 12.90285 12.90285 ZT20-23 11.945 11.945 11.945