Market Interest Rates: Higher interest rates can decrease the attractiveness of bonds, potentially lowering their prices. Conversely, lower rates can increase bond prices.

Credit Quality of Holdings: Downgrades in the credit ratings of bonds held by the fund can decrease their value and the overall fund price.

Economic Growth: Strong economic growth can sometimes lead to higher interest rates, affecting bond prices negatively. Slower growth might increase demand for safer assets like bonds.

Inflation Expectations: Rising inflation expectations can erode the real return of bonds, causing their prices to fall.

Fund Manager Performance: Skillful management and strategic allocation of assets within the fund can lead to better returns, increasing the fund's price. Ineffective management can do the opposite.

Investor Demand: High demand for FMRJX can push its price up, while low demand can lead to price declines.

Geopolitical Events: Significant global events and political instability can create uncertainty and affect bond markets, impacting fund prices.