The line chart depicts the differences in the average price of three commodities monthly, which are measured in percentages in 2014.
At the beginning of the year, copper and zinc had similar values of change in price at 1% and 2%, respectively. However, the highest percentage among the three was possessed by nickel at 6%. Then, all of them had constantly decreased gradually until June, as their lowest numbers for nickel, zinc, and copper were -3%, -1%, and -0.5%.
Having experienced a dip, they managed to get back in July with nickel at -1%, zinc at 0.5%, and copper at 1%. At the same time, their numbers were stagnant at their levels in that month to September before they had a slight decline in October and rose up again to similar points at the beginning of the year; except for nickel, which had drastically dropped to approximately the same value as the other metals that ranged between 1% and 2%.
To conclude, copper, nickel, and zinc experienced the lowest point in June, and nickel faced the most drastic downfall of price change among the others.