Fund Composition: NSAOX's price reflects the value of its underlying assets, primarily US government and agency mortgage-backed securities. Changes in these securities' prices directly impact NSAOX.

Interest Rate Movements: As a bond fund, NSAOX is highly sensitive to interest rate changes. Rising rates typically decrease bond values, thus lowering NSAOX's price, while falling rates tend to increase it.

Mortgage Prepayment Rates: Unexpectedly high mortgage prepayments can reduce the cash flow to NSAOX, potentially impacting its price negatively. Conversely, low prepayment rates can positively affect it.

Credit Risk Perception: Although primarily invested in government-backed securities, any perceived increase in credit risk within the mortgage market can negatively affect NSAOX's price, even if indirectly.

Inflation Expectations: Higher inflation expectations usually lead to increased interest rates, negatively impacting NSAOX's value. Lower inflation expectations can have the opposite effect.

Fund Flows: Significant investor inflows can increase demand, potentially raising the price, while outflows can create selling pressure, lowering the price.

Management Fees and Expenses: NSAOX's expense ratio directly reduces its returns. Higher expenses result in lower net asset value and potentially a lower price compared to similar funds with lower fees.

Economic Growth: A strong economy may lead to higher interest rates, indirectly affecting NSAOX's price negatively. Weaker economic conditions could lead to lower rates, potentially boosting its price.