MVIBKX.US is a mutual fund, so its price (Net Asset Value or NAV) is influenced by the performance of its underlying assets. Market Conditions: Broad market trends, economic growth, and investor sentiment significantly impact the fund's NAV as they affect the prices of the securities it holds.

Interest Rates: Changes in interest rates affect bond yields, which can impact the fund's fixed-income holdings and potentially influence its overall value.

Fund Holdings Performance: The specific stocks and bonds held by MVIBKX.US, and their individual performance, directly influence the fund's NAV.

Expense Ratio: The fund's operating expenses and management fees are deducted from the fund's assets, reducing the overall return and affecting the NAV.

Fund Flows: Significant inflows or outflows of investor money can impact the fund's trading activity and potentially influence its price.

Economic Indicators: Economic data releases, such as inflation reports, employment figures, and GDP growth, affect investor expectations and market valuations, indirectly influencing the fund's NAV.