condition mean min max ZT0-3 10.153305 10.153305 10.153305 ZT4-7 7.7659400000000005 7.7659400000000005 7.7659400000000005 ZT8-11 7.22415 7.22415 7.22415 ZT12-15 7.16817 7.16817 7.16817 ZT16-19 10.804535000000001 10.804535000000001 10.804535000000001 ZT20-23 11.2085 11.2085 11.2085