TDIFX vs. SSFNX

Last updated Jun 4, 2026

TDIFX (Dimensional Retirement Income Fund) and SSFNX (State Street Target Retirement Fund) are both Target Retirement Date funds. Over the past 10 years, TDIFX returned 5.12%/yr vs 5.89%/yr for SSFNX. Their correlation of 0.85 suggests significant overlap in exposure. TDIFX charges 0.06%/yr vs 0.10%/yr for SSFNX.

Performance

TDIFX vs. SSFNX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Dimensional Retirement Income Fund (TDIFX) and State Street Target Retirement Fund (SSFNX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, TDIFX achieves a 3.88% return, which is significantly lower than SSFNX's 5.58% return. Over the past 10 years, TDIFX has underperformed SSFNX with an annualized return of 5.12%, while SSFNX has yielded a comparatively higher 5.89% annualized return.

TDIFX

• 1D: 0.08%
• 1M: 1.22%
• YTD: 3.88%
• 6M: 3.88%
• 1Y: 8.34%
• 3Y*: 7.14%
• 5Y*: 5.13%
• 10Y*: 5.12%

SSFNX

• 1D: 0.17%
• 1M: 1.53%
• YTD: 5.58%
• 6M: 5.73%
• 1Y: 13.09%
• 3Y*: 9.93%
• 5Y*: 4.57%
• 10Y*: 5.89%

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

TDIFX vs. SSFNX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
TDIFX Dimensional Retirement Income Fund	3.88%	7.22%	6.21%	7.76%	-9.37%	14.53%	9.33%	9.96%	-1.98%	5.17%
SSFNX State Street Target Retirement Fund	5.58%	10.93%	7.05%	10.73%	-12.21%	6.87%	10.26%	13.97%	-2.49%	8.92%

Correlation

The correlation between TDIFX and SSFNX is 0.81, indicating a strong positive relationship between their price movements. Combining them offers limited diversification - they tend to fall together during downturns.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.81
Correlation (3Y) Calculated over the trailing 3-year period	0.88
Correlation (5Y) Calculated over the trailing 5-year period	0.88
Correlation (10Y) Calculated over the trailing 10-year period	0.85
Correlation (All Time) Calculated using the full available price history since Jan 5, 2016	0.85

The correlation between TDIFX and SSFNX has been stable across timeframes, ranging from 0.81 to 0.88 - a consistent structural relationship.

Return for Risk

TDIFX vs. SSFNX — Risk / Return Rank

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

TDIFX

TDIFX Risk / Return Rank: 83
TDIFX Sharpe Ratio Rank: 86
TDIFX Sortino Ratio Rank: 85
TDIFX Omega Ratio Rank: 84
TDIFX Calmar Ratio Rank: 78
TDIFX Martin Ratio Rank: 82

SSFNX

SSFNX Risk / Return Rank: 88
SSFNX Sharpe Ratio Rank: 90
SSFNX Sortino Ratio Rank: 90
SSFNX Omega Ratio Rank: 88
SSFNX Calmar Ratio Rank: 81
SSFNX Martin Ratio Rank: 88

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.

TDIFX vs. SSFNX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Dimensional Retirement Income Fund (TDIFX) and State Street Target Retirement Fund (SSFNX). 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.

	TDIFX	SSFNX	Difference
Sharpe ratio: Return per unit of total volatility	2.79	3.00	-0.21
Sortino ratio: Return per unit of downside risk	4.05	4.41	-0.36
Omega ratio: Gain probability vs. loss probability	1.57	1.62	-0.05
Calmar ratio: Return relative to maximum drawdown	3.56	3.73	-0.18
Martin ratio: Return relative to average drawdown	15.52	16.97	-1.46
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

TDIFX vs. SSFNX - Sharpe Ratio Comparison

The current TDIFX Sharpe Ratio is 2.79, which is comparable to the SSFNX Sharpe Ratio of 3.00. The chart below compares the historical Sharpe Ratios of TDIFX and SSFNX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Sharpe Ratios by Period

	TDIFX	SSFNX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.79	3.00	-0.21
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.89	0.70	+0.19
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	1.02	0.90	+0.12
Sharpe Ratio (All Time) Calculated using the full available price history	1.06	0.84	+0.22

Drawdowns

TDIFX vs. SSFNX - Drawdown Comparison

The maximum TDIFX drawdown since its inception was -12.21%, smaller than the maximum SSFNX drawdown of -16.62%. Use the drawdown chart below to compare losses from any high point for TDIFX and SSFNX.

Drawdown Indicators

	TDIFX	SSFNX	Difference
Max Drawdown Largest peak-to-trough decline	-12.21%	-16.62%	+4.41%
Max Drawdown (1Y) Largest decline over 1 year	-2.61%	-3.52%	+0.91%
Max Drawdown (3Y) Largest decline over 3 years	-3.51%	-5.40%	+1.89%
Max Drawdown (5Y) Largest decline over 5 years	-12.21%	-16.62%	+4.41%
Max Drawdown (10Y) Largest decline over 10 years	-12.21%	-16.62%	+4.41%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-1.75%	-2.52%	+0.77%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.58%	0.77%	-0.19%

Volatility

TDIFX vs. SSFNX - Volatility Comparison

The current volatility for Dimensional Retirement Income Fund (TDIFX) is 1.01%, while State Street Target Retirement Fund (SSFNX) has a volatility of 1.41%. This indicates that TDIFX experiences smaller price fluctuations and is considered to be less risky than SSFNX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	TDIFX	SSFNX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.01%	1.41%	-0.40%
Volatility (6M) Calculated over the trailing 6-month period	2.49%	3.53%	-1.04%
Volatility (1Y) Calculated over the trailing 1-year period	3.33%	4.38%	-1.05%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	5.89%	6.58%	-0.69%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	5.06%	6.57%	-1.51%

TDIFX vs. SSFNX - Expense Ratio Comparison

TDIFX has a 0.06% expense ratio, which is lower than SSFNX's 0.10% 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

TDIFX vs. SSFNX - Dividend Comparison

TDIFX's dividend yield for the trailing twelve months is around 1.99%, less than SSFNX's 4.61% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
SSFNX State Street Target Retirement Fund	4.61%	4.86%	5.78%	5.26%	5.12%	6.69%	1.61%	3.35%	4.40%	2.72%	1.84%	2.05%
TDIFX Dimensional Retirement Income Fund	1.99%	1.77%	3.11%	3.09%	4.66%	9.39%	1.39%	1.98%	2.11%	0.98%	0.89%	0.00%

Frequently Asked Questions

Can I hold both TDIFX and SSFNX in my portfolio?

TDIFX and SSFNX have a correlation of 0.81, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, TDIFX or SSFNX?

SSFNX has higher volatility (1.41%) compared to TDIFX (1.01%). In terms of maximum drawdown, TDIFX dropped -12.21% vs SSFNX's -16.62%.

Which has better risk-adjusted returns?

SSFNX currently has the higher Sharpe Ratio (3.00 vs 2.79), 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.