SPAXX vs. ^CASHX

Last updated Apr 2, 2026

Compare and contrast key facts about Fidelity Government Money Market Fund (SPAXX) and US Money Market Index (^CASHX).

SPAXX is managed by Fidelity. It was launched on Feb 5, 1990.

Performance

SPAXX vs. ^CASHX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Government Money Market Fund (SPAXX) and US Money Market Index (^CASHX). The values are adjusted to include any dividend payments, if applicable.

SPAXX vs. ^CASHX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021
SPAXX Fidelity Government Money Market Fund	0.53%	3.96%	1.54%	0.41%	0.00%	0.00%
^CASHX US Money Market Index	0.89%	4.21%	5.16%	5.03%	1.68%	0.05%

Returns By Period

In the year-to-date period, SPAXX achieves a 0.53% return, which is significantly lower than ^CASHX's 0.89% return.

SPAXX

• 1D: 0.00%
• 1M: 0.00%
• YTD: 0.53%
• 6M: 1.46%
• 1Y: 3.49%
• 3Y*: 2.14%
• 5Y*: —
• 10Y*: —

^CASHX

• 1D: 0.01%
• 1M: 0.28%
• YTD: 0.89%
• 6M: 1.85%
• 1Y: 4.03%
• 3Y*: 4.72%
• 5Y*: 3.39%
• 10Y*: 2.26%

*Multi-year figures are annualized to reflect compound growth (CAGR)

Return for Risk

SPAXX vs. ^CASHX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Government Money Market Fund (SPAXX) and US Money Market Index (^CASHX). Risk-adjusted metrics are performance indicators that assess an investment's returns in relation to its risk, enabling a more accurate comparison of different investment options.

	SPAXX	^CASHX	Difference
Sharpe ratio Return per unit of total volatility	3.48	265.80	-262.32
Sortino ratio Return per unit of downside risk	—	—	—
Omega ratio Gain probability vs. loss probability	—	—	—
Calmar ratio Return relative to maximum drawdown	—	—	—
Martin ratio Return relative to average drawdown	—	—	—
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

SPAXX vs. ^CASHX - Sharpe Ratio Comparison

The current SPAXX Sharpe Ratio is 3.48, which is lower than the ^CASHX Sharpe Ratio of 265.80. The chart below compares the historical Sharpe Ratios of SPAXX and ^CASHX, offering insights into how both investments have performed under varying market conditions. These values are calculated using daily returns over the previous 12 months.

Sharpe Ratios by Period

	SPAXX	^CASHX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	3.48	265.80	-262.32
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	—	33.37	—
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	23.27	—
Sharpe Ratio (All Time) Calculated using the full available price history	2.01	25.97	-23.96

Correlation

The correlation between SPAXX and ^CASHX is 0.01, which is considered to be low. This implies their price changes are not closely related. A low correlation is generally favorable for portfolio diversification, as it helps to reduce overall risk by spreading it across multiple assets with different performance patterns.

Drawdowns

SPAXX vs. ^CASHX - Drawdown Comparison

The maximum SPAXX drawdown since its inception was 0.00%, which is greater than ^CASHX's maximum drawdown of 0.00%. Use the drawdown chart below to compare losses from any high point for SPAXX and ^CASHX.

Drawdown Indicators

	SPAXX	^CASHX	Difference
Max Drawdown Largest peak-to-trough decline	0.00%	0.00%	0.00%
Max Drawdown (1Y) Largest decline over 1 year	0.00%	0.00%	0.00%
Max Drawdown (5Y) Largest decline over 5 years	—	0.00%	—
Max Drawdown (10Y) Largest decline over 10 years	—	0.00%	—
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	0.00%	0.00%	0.00%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.00%	0.00%	0.00%

Volatility

SPAXX vs. ^CASHX - Volatility Comparison

The current volatility for Fidelity Government Money Market Fund (SPAXX) is 0.00%, while US Money Market Index (^CASHX) has a volatility of 0.00%. This indicates that SPAXX experiences smaller price fluctuations and is considered to be less risky than ^CASHX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	SPAXX	^CASHX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.00%	0.00%	0.00%
Volatility (6M) Calculated over the trailing 6-month period	0.71%	0.01%	+0.70%
Volatility (1Y) Calculated over the trailing 1-year period	1.08%	0.01%	+1.07%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	0.67%	0.08%	+0.59%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	0.67%	0.08%	+0.59%