Interest Rates: MMWFX.US, being a money market fund, is heavily influenced by prevailing interest rates. Higher rates generally lead to higher yields and a corresponding increase in share price, and vice versa.

Credit Quality: The creditworthiness of the securities held within MMWFX.US impacts its perceived risk. Lower credit quality assets may decrease the share price.

Fund Expenses: The fund's expense ratio, which covers management fees and operating costs, directly affects the net return to investors and therefore, the share price.

Supply and Demand: Basic economic principles apply. Increased demand for MMWFX.US shares can push the price higher, while increased selling pressure can lead to price declines.

Economic Conditions: Broad economic factors, such as inflation and overall economic growth, can influence interest rate expectations and affect the fund's attractiveness.

Regulatory Changes: Changes in regulations governing money market funds can impact their investment strategies and risk profiles, potentially affecting share price.