U.S. equities opened higher Tuesday after the U.S. Treasury Department said it would at least double buybacks of longer-term Treasury bonds, increasing each operation from $2 billion to a minimum of $4 billion starting September 9. The announcement briefly drove the 10-year Treasury yield down from 4.71% to 4.64%, supporting valuations after the S&P 500 reached a record the previous week and then suffered a four-session losing streak. The S&P 500 rose about 0.2% to roughly 7,708, while the Dow Jones Industrial Average gained about 120 points to approximately 53,463 and the Nasdaq posted modest gains. The relief proved temporary: By August 20 and 21, the 10-year yield had moved back toward 4.7%, while the S&P 500 fell about 0.9% and the Dow lost around 1.3%. Analysts characterized the buyback plan as a short-term measure rather than a solution to expanding government debt, elevated Treasury issuance, inflation expectations, rising oil prices and geopolitical uncertainty linked particularly to Iran. Strong corporate earnings offered some support, although higher Treasury yields reduce the present value of future corporate cash flows and can pressure stock valuations even when businesses remain healthy.