The given graph represents data about the standard monthly percentage change in the cost of copper, nickel, and zinc throughout 2014.
Overall, what stands out from the graph is that the price of nickel, which started the year with the highest increase, experienced the most dramatic decline, while zinc, initially the lowest, ended the year with the greatest growth. Another interesting point is that, during July to September, all three trends remained unchanged.
Turning to the details, the price of nickel started at 6% and during the following three months, it declined rapidly to 1%. During the next three months, there was no significant change, with only a slight drop in May to approximately 0.5%. Just in one month, from May to June, the price of nickel plunged, hitting a trough at exactly -3%.
On the other hand, the figure for zinc began from the lowest point at 1%, rose to 3% in February, and then declined steadily to 1% by May. From May until the end of the trend, the expenses for zinc and nickel showed similarities. Both first decreased, then increased, and remained stable for three months at around -1% and -0.5% for nickel and zinc, respectively. Afterwards, they both experienced another drop followed by growth. The price of zinc had risen to the highest point, reaching 2% by December.
In terms of the price of copper, there was a decrease until June at roughly -0.5%, then it rose slightly and remained at 1% during July and September. By the end of the year, it had reached about 1.5%, exceeding nickel.