STDAX vs. SPIIX

Last updated Apr 1, 2026

Compare and contrast key facts about SEI Asset Allocation Trust Defensive Strategy Allocation Fund (STDAX) and SEI S&P 500 Index Fund Class I (SPIIX).

STDAX is managed by SEI. It was launched on Nov 16, 2003. SPIIX is a passively managed fund by SEI that tracks the performance of the S&P 500 Index. It was launched on Jun 28, 2002.

Performance

STDAX vs. SPIIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in SEI Asset Allocation Trust Defensive Strategy Allocation Fund (STDAX) and SEI S&P 500 Index Fund Class I (SPIIX). The values are adjusted to include any dividend payments, if applicable.

STDAX vs. SPIIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
STDAX SEI Asset Allocation Trust Defensive Strategy Allocation Fund	0.36%	4.46%	5.35%	4.45%	-1.58%	1.56%	-19.54%	19.83%	-3.32%	9.70%
SPIIX SEI S&P 500 Index Fund Class I	-7.22%	16.97%	24.11%	25.49%	-18.84%	28.04%	17.66%	30.72%	-5.00%	21.06%

Returns By Period

In the year-to-date period, STDAX achieves a 0.36% return, which is significantly higher than SPIIX's -7.22% return. Over the past 10 years, STDAX has underperformed SPIIX with an annualized return of 2.52%, while SPIIX has yielded a comparatively higher 12.99% annualized return.

STDAX

• 1D: 0.09%
• 1M: -0.18%
• YTD: 0.36%
• 6M: 1.30%
• 1Y: 3.90%
• 3Y*: 4.41%
• 5Y*: 2.77%
• 10Y*: 2.52%

SPIIX

• 1D: -0.40%
• 1M: -7.73%
• YTD: -7.22%
• 6M: -5.00%
• 1Y: 13.56%
• 3Y*: 16.34%
• 5Y*: 10.62%
• 10Y*: 12.99%

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

STDAX vs. SPIIX - Expense Ratio Comparison

STDAX has a 0.35% expense ratio, which is lower than SPIIX's 0.65% expense ratio.

SPIIX

SEI S&P 500 Index Fund Class I

STDAX

SEI Asset Allocation Trust Defensive Strategy Allocation Fund

Return for Risk

STDAX vs. SPIIX — Risk / Return Rank

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

STDAX

STDAX Risk / Return Rank: 99
STDAX Sharpe Ratio Rank: 100
STDAX Sortino Ratio Rank: 99
STDAX Omega Ratio Rank: 99
STDAX Calmar Ratio Rank: 99
STDAX Martin Ratio Rank: 99

SPIIX

SPIIX Risk / Return Rank: 40
SPIIX Sharpe Ratio Rank: 35
SPIIX Sortino Ratio Rank: 38
SPIIX Omega Ratio Rank: 43
SPIIX Calmar Ratio Rank: 37
SPIIX Martin Ratio Rank: 48

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.

STDAX vs. SPIIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for SEI Asset Allocation Trust Defensive Strategy Allocation Fund (STDAX) and SEI S&P 500 Index Fund Class I (SPIIX). 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.

	STDAX	SPIIX	Difference
Sharpe ratio Return per unit of total volatility	4.24	0.79	+3.45
Sortino ratio Return per unit of downside risk	7.10	1.23	+5.87
Omega ratio Gain probability vs. loss probability	2.50	1.19	+1.31
Calmar ratio Return relative to maximum drawdown	6.50	0.98	+5.51
Martin ratio Return relative to average drawdown	31.36	4.73	+26.63
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

STDAX vs. SPIIX - Sharpe Ratio Comparison

The current STDAX Sharpe Ratio is 4.24, which is higher than the SPIIX Sharpe Ratio of 0.79. The chart below compares the historical Sharpe Ratios of STDAX and SPIIX, 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

	STDAX	SPIIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	4.24	0.79	+3.45
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	1.42	0.58	+0.84
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.38	0.69	-0.31
Sharpe Ratio (All Time) Calculated using the full available price history	-0.00	0.53	-0.53

Correlation

The correlation between STDAX and SPIIX is 0.73, which is considered to be high. That indicates a strong positive relationship between their price movements. Having highly-correlated positions in a portfolio may signal a lack of diversification, potentially leading to increased risk during market downturns.

Dividends

STDAX vs. SPIIX - Dividend Comparison

STDAX's dividend yield for the trailing twelve months is around 4.47%, less than SPIIX's 9.08% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
STDAX SEI Asset Allocation Trust Defensive Strategy Allocation Fund	4.47%	4.49%	4.97%	4.77%	3.54%	0.87%	1.71%	5.19%	8.53%	6.92%	10.19%	3.84%
SPIIX SEI S&P 500 Index Fund Class I	9.08%	8.42%	12.20%	4.10%	10.27%	7.03%	5.78%	4.04%	3.90%	2.08%	4.34%	1.53%

Drawdowns

STDAX vs. SPIIX - Drawdown Comparison

The maximum STDAX drawdown since its inception was -76.81%, which is greater than SPIIX's maximum drawdown of -55.78%. Use the drawdown chart below to compare losses from any high point for STDAX and SPIIX.

Drawdown Indicators

	STDAX	SPIIX	Difference
Max Drawdown Largest peak-to-trough decline	-76.81%	-55.78%	-21.03%
Max Drawdown (1Y) Largest decline over 1 year	-0.59%	-12.14%	+11.55%
Max Drawdown (5Y) Largest decline over 5 years	-2.91%	-25.70%	+22.79%
Max Drawdown (10Y) Largest decline over 10 years	-26.89%	-33.85%	+6.96%
Current Drawdown Current decline from peak	-9.55%	-9.02%	-0.53%
Average Drawdown Average peak-to-trough decline	-31.95%	-7.33%	-24.62%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.12%	2.52%	-2.40%

Volatility

STDAX vs. SPIIX - Volatility Comparison

The current volatility for SEI Asset Allocation Trust Defensive Strategy Allocation Fund (STDAX) is 0.39%, while SEI S&P 500 Index Fund Class I (SPIIX) has a volatility of 4.24%. This indicates that STDAX experiences smaller price fluctuations and is considered to be less risky than SPIIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	STDAX	SPIIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.39%	4.24%	-3.85%
Volatility (6M) Calculated over the trailing 6-month period	0.64%	9.09%	-8.45%
Volatility (1Y) Calculated over the trailing 1-year period	0.93%	18.13%	-17.20%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	1.95%	18.41%	-16.46%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	6.69%	18.84%	-12.15%