condition mean min max ZT0-3 6.8518799999999995 6.8518799999999995 6.8518799999999995 ZT4-7 6.772245 6.772245 6.772245 ZT8-11 5.128255 5.128255 5.128255 ZT12-15 5.142659999999999 5.142659999999999 5.142659999999999 ZT16-19 6.408205000000001 6.408205000000001 6.408205000000001 ZT20-23 5.73508 5.73508 5.73508