condition mean min max ZT0-3 1.597419 1.197357 2.219795 ZT4-7 1.05331 1.05331 1.05331 ZT8-11 0.6059785 0.6059785 0.6059785 ZT12-15 4.709905 4.0023 5.41751 ZT16-19 3.42869 3.42869 3.42869 ZT20-23 2.122375 2.122375 2.122375