Market Interest Rates: Higher interest rates generally decrease bond prices, as newly issued bonds offer more attractive yields, making existing bonds (like those held by VWTJX) less desirable.

Economic Growth: Strong economic growth can lead to inflation and higher interest rates, which can negatively impact bond prices. Conversely, slow economic growth or recession fears might increase demand for bonds, pushing prices up.

Inflation Expectations: Rising inflation erodes the purchasing power of future bond payments, causing investors to demand higher yields and thus lower bond prices. Stable or decreasing inflation expectations typically support bond prices.

Federal Reserve Policy: Actions by the Federal Reserve, such as adjusting the federal funds rate or engaging in quantitative easing/tightening, have a significant impact on interest rates and bond yields, directly influencing the price of VWTJX.

Credit Risk: Changes in the perceived creditworthiness of bond issuers (e.g., U.S. Treasury) can affect bond prices. Higher credit risk leads to lower bond prices, while improved creditworthiness can boost prices.

Supply and Demand: The overall supply of and demand for U.S. Treasury bonds will affect prices. Increased Treasury issuance can put downward pressure on prices, while strong investor demand can drive prices higher.

Global Economic Conditions: Global events and economic conditions can impact U.S. bond prices. For example, economic uncertainty in other countries might lead to a "flight to safety," increasing demand for U.S. Treasuries and pushing prices up.