Market Interest Rates: Higher interest rates often make bonds less attractive, potentially lowering the price of FOTSMX.US, as investors seek higher yields elsewhere.

Credit Risk: Changes in the perceived creditworthiness of the bonds held within the fund directly impact its value. Downgrades can lower the price.

Economic Conditions: Economic growth or recession can influence investor sentiment towards bonds. Stronger economies might lead to bond selling.

Inflation Expectations: Rising inflation erodes the real value of fixed income, typically leading to lower bond prices and, therefore, a lower FOTSMX.US price.

Supply and Demand: The basic principles of supply and demand apply. Increased selling pressure without matching buying interest will drive the price down.

Fund Management: The skill of the fund managers and their investment decisions affect the fund's overall performance and, consequently, its price.

Bond Maturities: Funds with longer maturities are more sensitive to interest rate changes, influencing price volatility. Longer maturities lead to higher volatility.

Liquidity of Underlying Bonds: Illiquid bond holdings can make it harder to accurately price FOTSMX.US, impacting its ability to accurately reflect its net asset value.

Geopolitical Events: Global political or economic instability can trigger risk-off sentiment, leading to bond selling and a subsequent price decline in FOTSMX.US.

Currency Fluctuations: For funds holding international bonds, currency fluctuations can impact the fund's value when converted back to USD, either positively or negatively.

Fund Expense Ratio: Higher expense ratios can negatively affect the fund's net return and potentially make it less attractive, affecting the price over time.

Investor Sentiment: Overall market mood and investor confidence play a role. Negative sentiment can trigger broad market sell-offs, including FOTSMX.US.