condition mean min max ZT0-3 1.3432451666666667 0.8749565 1.7576900000000002 ZT4-7 0.670531 0.670531 0.670531 ZT8-11 0.3901865 0.3901865 0.3901865 ZT12-15 0.51731675 0.38140450000000004 0.6532290000000001 ZT16-19 0.6714935 0.6714935 0.6714935 ZT20-23 0.8279110000000001 0.8279110000000001 0.8279110000000001