condition mean min max ZT0-3 1.500375 1.4041000000000001 1.6541299999999999 ZT4-7 2.131825 2.131825 2.131825 ZT8-11 2.058065 2.058065 2.058065 ZT12-15 3.000065 2.712395 3.287735 ZT16-19 2.477965 2.477965 2.477965 ZT20-23 2.324985 2.324985 2.324985