condition mean min max ZT0-3 4.31969 4.31969 4.31969 ZT4-7 7.539305000000001 7.539305000000001 7.539305000000001 ZT8-11 6.62121 6.62121 6.62121 ZT12-15 6.308495000000001 6.308495000000001 6.308495000000001 ZT16-19 3.60585 3.60585 3.60585 ZT20-23 3.133175 3.133175 3.133175