SSAFX vs. STFAX

Last updated Jun 25, 2026

SSAFX (State Street Aggregate Bond Index Portfolio) and STFAX (State Street Equity 500 Index Fund) are both mutual funds - SSAFX is a Intermediate Core Bond fund managed by State Street, while STFAX is a Large Cap Blend Equities fund managed by State Street. Over the past 10 years, SSAFX returned 27.76%/yr vs 15.39%/yr for STFAX. At a correlation of -0.05, they often move in opposite directions. SSAFX charges 0.02%/yr vs 0.17%/yr for STFAX.

Performance

SSAFX vs. STFAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in State Street Aggregate Bond Index Portfolio (SSAFX) and State Street Equity 500 Index Fund (STFAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, SSAFX achieves a 0.45% return, which is significantly lower than STFAX's 8.13% return. Over the past 10 years, SSAFX has outperformed STFAX with an annualized return of 27.76%, while STFAX has yielded a comparatively lower 15.39% annualized return.

SSAFX

• 1D: 0.12%
• 1M: 0.73%
• YTD: 0.45%
• 6M: 0.37%
• 1Y: 4.01%
• 3Y*: 3.84%
• 5Y*: -0.04%
• 10Y*: 27.76%

STFAX

• 1D: -1.43%
• 1M: -1.34%
• YTD: 8.13%
• 6M: 6.80%
• 1Y: 22.13%
• 3Y*: 20.60%
• 5Y*: 12.94%
• 10Y*: 15.39%

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

SSAFX vs. STFAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
SSAFX State Street Aggregate Bond Index Portfolio	0.45%	6.81%	1.34%	5.61%	-13.30%	-1.72%	978.57%	8.69%	-0.12%	3.38%
STFAX State Street Equity 500 Index Fund	8.13%	17.63%	24.80%	26.09%	-18.28%	28.31%	18.14%	31.13%	-4.52%	21.43%

Correlation

The correlation between SSAFX and STFAX is 0.32, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.32
Correlation (3Y) Calculated over the trailing 3-year period	0.22
Correlation (5Y) Calculated over the trailing 5-year period	0.15
Correlation (10Y) Calculated over the trailing 10-year period	0.01
Correlation (All Time) Calculated using the full available price history since Sep 22, 2014	-0.05

The correlation between SSAFX and STFAX shifts across timeframes, from -0.05 (all time) to 0.32 (1 year), reflecting how their relationship changes across market environments.

Return for Risk

SSAFX vs. STFAX — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.

SSAFX

SSAFX Risk / Return Rank: 22
SSAFX Sharpe Ratio Rank: 22
SSAFX Sortino Ratio Rank: 23
SSAFX Omega Ratio Rank: 20
SSAFX Calmar Ratio Rank: 23
SSAFX Martin Ratio Rank: 20

STFAX

STFAX Risk / Return Rank: 56
STFAX Sharpe Ratio Rank: 53
STFAX Sortino Ratio Rank: 49
STFAX Omega Ratio Rank: 51
STFAX Calmar Ratio Rank: 57
STFAX Martin Ratio Rank: 69

The rank (0–100) shows how this investment's returns compare to the risk taken. Higher = better. Based on the past 12 months of data, combining Sharpe, Sortino, and other metrics used by quantitative funds and institutional investors.

SSAFX vs. STFAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for State Street Aggregate Bond Index Portfolio (SSAFX) and State Street Equity 500 Index Fund (STFAX). 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.

Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.

	SSAFX	STFAX	Difference
Sharpe ratio: Return per unit of total volatility	1.19	1.88	-0.70
Sortino ratio: Return per unit of downside risk	1.78	2.57	-0.79
Omega ratio: Gain probability vs. loss probability	1.21	1.34	-0.13
Calmar ratio: Return relative to maximum drawdown	1.59	2.65	-1.05
Martin ratio: Return relative to average drawdown	4.55	11.89	-7.34

SSAFX vs. STFAX - Sharpe Ratio Comparison

The current SSAFX Sharpe Ratio is 1.19, which is lower than the STFAX Sharpe Ratio of 1.88. The chart below compares the historical Sharpe Ratios of SSAFX and STFAX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Drawdowns

SSAFX vs. STFAX - Drawdown Comparison

The maximum SSAFX drawdown since its inception was -18.74%, smaller than the maximum STFAX drawdown of -57.29%. Use the drawdown chart below to compare losses from any high point for SSAFX and STFAX.

Drawdown Indicators

	SSAFX	STFAX	Difference
Max Drawdown Largest peak-to-trough decline	-18.74%	-57.29%	+38.55%
Max Drawdown (1Y) Largest decline over 1 year	-2.74%	-8.91%	+6.17%
Max Drawdown (3Y) Largest decline over 3 years	-6.09%	-18.76%	+12.67%
Max Drawdown (5Y) Largest decline over 5 years	-18.10%	-24.57%	+6.47%
Max Drawdown (10Y) Largest decline over 10 years	-18.74%	-33.76%	+15.02%
Current Drawdown Current decline from peak	-2.58%	-3.13%	+0.55%
Average Drawdown Average peak-to-trough decline	-4.40%	-10.19%	+5.79%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.96%	1.98%	-1.02%

Volatility

SSAFX vs. STFAX - Volatility Comparison

The current volatility for State Street Aggregate Bond Index Portfolio (SSAFX) is 1.08%, while State Street Equity 500 Index Fund (STFAX) has a volatility of 4.89%. This indicates that SSAFX experiences smaller price fluctuations and is considered to be less risky than STFAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	SSAFX	STFAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.08%	4.89%	-3.81%
Volatility (6M) Calculated over the trailing 6-month period	2.73%	9.92%	-7.19%
Volatility (1Y) Calculated over the trailing 1-year period	3.69%	12.56%	-8.87%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	5.95%	16.99%	-11.04%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	277.57%	18.05%	+259.52%

SSAFX vs. STFAX - Expense Ratio Comparison

SSAFX has a 0.02% expense ratio, which is lower than STFAX's 0.17% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

SSAFX vs. STFAX - Dividend Comparison

SSAFX's dividend yield for the trailing twelve months is around 4.16%, more than STFAX's 1.19% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
SSAFX State Street Aggregate Bond Index Portfolio	4.16%	3.70%	3.76%	3.16%	2.49%	1.90%	2.41%	2.88%	2.82%	2.42%	2.21%	3.21%
STFAX State Street Equity 500 Index Fund	1.19%	1.29%	1.47%	1.63%	2.01%	2.61%	1.71%	4.28%	5.02%	5.78%	1.92%	1.69%

Frequently Asked Questions

Can I hold both SSAFX and STFAX in my portfolio?

SSAFX and STFAX have a correlation of 0.32, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, SSAFX or STFAX?

STFAX has higher volatility (4.89%) compared to SSAFX (1.08%). In terms of maximum drawdown, SSAFX dropped -18.74% vs STFAX's -57.29%.

Which has better risk-adjusted returns?

STFAX currently has the higher Sharpe Ratio (1.88 vs 1.19), meaning it's delivered slightly more return per unit of risk over the trailing 12 months. However, this ranking shifts over time - use the Risk/Return Score above for a more comprehensive view that combines Sharpe, Sortino, and other measures used by quantitative funds.