Market Interest Rates: Rising interest rates often lead to lower bond prices as newly issued bonds offer higher yields, making older bonds less attractive.

Credit Risk: Changes in the perceived creditworthiness of the bond issuers held by FDBAX influence its price. Downgrades lead to price declines.

Inflation Expectations: Rising inflation expectations erode the real value of fixed income investments, causing bond prices in FDBAX to fall.

Economic Growth: Strong economic growth can lead to higher interest rates and inflation, both negatively impacting bond prices in FDBAX.

Fund Management Decisions: The fund manager's skill in selecting bonds and managing duration impacts the fund's overall performance and price.

Supply and Demand: The overall demand for FDBAX shares, relative to the available supply, can influence its market price.

Maturity of Bonds: Longer-maturity bonds are more sensitive to interest rate changes than shorter-maturity bonds, affecting FDBAX's price if it holds many long-dated bonds.