The Rio Tinto Ltd (ASX: RIO) share price slipped 4.7% in May.
Shares in the S&P/ASX 200 Index (ASX: XJO) miner closed April trading at $112.25 a share. On 31 May, Rio shares finished the day trading for $107.00.
The 4.7% slide in the Rio Tinto share price lagged the ASX 200, with the benchmark index losing 3% in May.
But Rio Tinto wasn't the only underperformer for the month.
Fortescue Metals Group Ltd (ASX: FMG) and BHP Group Ltd (ASX: BHP) shares also lost significantly more than the benchmark index.
Here's why.
What were ASX 200 investors considering in May?
With no price-sensitive news released during the month, the sizeable retrace in the Rio Tinto share price looks to be largely linked to commodity prices.
Iron ore is the biggest revenue earner for Rio Tinto.
In 2022, the steel-making metal contributed US$18.6 billion to the miner's earnings before interest, taxes, depreciation and amortisation (EBITDA). That's 69% of the company's total earnings.
Iron ore kicked off May trading for approximately US$105 per tonne. By the end of the month, that same tonne was fetching around US$100 per tonne. The 4.8% price slide is almost in line with the drop in the Rio Tinto share price.
The iron ore price has come under pressure amid weaker-than-forecast demand from China's steel factories. This prompted analysts at Citi to forecast the price could fall to US$90 per tonne before finding support.
What else impacted the Rio Tinto share price in May?
Atop the broader market retrace and falling iron ore prices, Rio Tinto wasn't helped by falling copper prices over the month either.
The red metal ended April trading for US$8,596 per tonne and finished off May trading for US$8,089 per tonne, down 5.9%.
While the revenue Rio Tinto derives from its copper segment is overshadowed by its iron ore division, it's not insignificant.
In 2022, copper brought in US$2.4 billion of underlying EBITDA, or 8.8% of the ASX 200 miner's total earnings.
