Bond Yields: TLGUX invests in U.S. government securities, so changes in prevailing interest rates, especially U.S. Treasury yields, significantly affect its price. Higher yields decrease the fund's value.

Credit Risk: Though investing in U.S. government bonds, concerns about the U.S.'s creditworthiness or fiscal stability can impact demand, affecting the fund's price.

Inflation: Inflation erodes the real value of fixed income investments. Rising inflation expectations can lead to lower bond prices and thus a lower TLGUX value.

Economic Growth: Strong economic growth may lead to higher interest rates as the Federal Reserve tightens monetary policy, negatively affecting the fund's price.

Federal Reserve Policy: The Federal Reserve's monetary policy decisions, such as interest rate hikes or quantitative easing, have a direct influence on bond yields and TLGUX's value.

Investor Sentiment: Overall investor risk appetite and sentiment toward fixed income investments can influence demand for TLGUX, affecting its price.

Fund Flows: Large inflows or outflows from the fund can put upward or downward pressure on its price, although this is usually a short-term effect.

Maturity & Duration: TLGUX's price sensitivity to interest rate changes is determined by the average maturity and duration of its bond holdings. Longer durations mean greater price fluctuations.