condition mean min max ZT0-3 9.520145 9.32843 9.71186 ZT4-7 9.36487 9.36487 9.36487 ZT8-11 8.409905 8.409905 8.409905 ZT12-15 0 0 0 ZT16-19 8.85306 8.85306 8.85306 ZT20-23 10.215435 10.215435 10.215435