condition mean min max ZT0-3 8.265172499999998 7.5678149999999995 8.96253 ZT4-7 6.29526 6.29526 6.29526 ZT8-11 7.066129999999999 7.066129999999999 7.066129999999999 ZT12-15 0 0 0 ZT16-19 10.251650000000001 10.251650000000001 10.251650000000001 ZT20-23 7.4524550000000005 7.4524550000000005 7.4524550000000005