condition mean min max ZT0-3 3.7238976666666663 1.166628 5.11086 ZT4-7 1.749501 1.749501 1.749501 ZT8-11 1.360921 1.360921 1.360921 ZT12-15 3.3627424999999995 3.09318 3.6323049999999997 ZT16-19 3.985685 3.985685 3.985685 ZT20-23 5.740114999999999 5.740114999999999 5.740114999999999