Underlying Asset Performance: The price of MMXAX.US is primarily driven by the performance of the stocks it holds. Strong stock performance leads to a higher fund value.

Interest Rate Movements: Changes in interest rates can affect the valuation of the fund's bond holdings and influence stock valuations, thereby impacting the overall price.

Market Sentiment: General investor optimism or pessimism can significantly affect the demand for and price of MMXAX.US, especially during periods of market volatility.

Fund Manager Skill: The fund manager's ability to select profitable investments and manage risk contributes to the overall return and price of the fund.

Economic Conditions: Factors like GDP growth, inflation, and unemployment rates can influence corporate earnings and market sentiment, thus affecting the fund's price.

Geopolitical Events: Global events such as political instability, trade wars, or regulatory changes can impact investor confidence and the performance of the fund's holdings.

Expense Ratio and Fees: The costs associated with managing the fund, including the expense ratio, directly impact the fund's net asset value and thus its price.

Supply and Demand: High demand for the fund can drive up its price, while increased selling pressure can lead to a price decrease.

Dividend Payments: Dividend payouts from the underlying stocks held in the fund can influence the fund's total return and potentially its price.

Currency Fluctuations: If the fund holds international assets, currency exchange rate changes can affect the value of those assets and, consequently, the fund's price.