condition mean min max ZT0-3 4.2919625 4.014215 4.569710000000001 ZT4-7 6.0180299999999995 6.0180299999999995 6.0180299999999995 ZT8-11 5.6985600000000005 5.6985600000000005 5.6985600000000005 ZT12-15 0 0 0 ZT16-19 4.29371 4.29371 4.29371 ZT20-23 6.04999 6.04999 6.04999