Complex sentence: In 2016, Kinross'credit rating was lowered to "Junk" status by Standard & Poor's, the decision was largely based on the share of their production that came from mines in Russia, which it saw as a significant risk.
Split into simpler sentences: In 2016, Kinross'credit rating was lowered to "Junk" status by Standard & Poor's. The decision was largely based on the share of their production that came from mines in Russia, which it saw as a significant risk.