In more normal times, the direction of commodity prices, and oil in particular, had an impact of the direction of bond yields. That because oil is viewed as an early barometer of inflationary trends. A falling oil price (along with other commodities) was disinflationary which boosted bond prices and lowered bond yields. Rising oil had the opposite effect — falling bond prices and rising yields. Rising oil prices often prompted the Fed to raise rates to combat the threat of inflation. That’s not necessarily the case now, but some semblance of those old relationships may still hold.