condition mean min max ZT0-3 10.183876 10.183876 10.183876 ZT4-7 9.424445 9.424445 9.424445 ZT8-11 9.638584999999999 9.638584999999999 9.638584999999999 ZT12-15 9.538357000000001 9.538357000000001 9.538357000000001 ZT16-19 9.886286 9.886286 9.886286 ZT20-23 10.102332 10.102332 10.102332