Why the Rio Tinto (ASX:RIO) share price is among the worst performers today

As the S&P/ASX 200 Index (ASX: XJO) creeps back into the realm of negatives this afternoon, it’s worth taking a look at which shares are pulling it down the most. Upon inspection, we can see that both the Rio Tinto Ltd (ASX: RIO) share price and the Fortescue Metals Group Ltd (ASX: FMG) share price are in the bottom three of the top 200. Nufarm Ltd (ASX: NUF) is currently sitting squarely in the middle to complete the red trifecta.

Given there’s no news out from Nufarm, potentially shareholders are taking some profits after the recent run-up. In contrast, there’s plenty to talk about from Rio and Fortescue.

So, why are these…