condition mean min max ZT0-3 8.2819875 7.54078 9.023195000000001 ZT4-7 6.23013 6.23013 6.23013 ZT8-11 7.695975 7.695975 7.695975 ZT12-15 0 0 0 ZT16-19 9.048314999999999 9.048314999999999 9.048314999999999 ZT20-23 7.889855000000001 7.889855000000001 7.889855000000001