SOKAX vs. SPIIX

Last updated Jun 4, 2026

SOKAX (SEI Asset Allocation Trust Core Market Strategy Fund) and SPIIX (SEI S&P 500 Index Fund Class I) are both mutual funds - SOKAX is a Diversified Portfolio fund managed by SEI, while SPIIX is a Large Cap Blend Equities fund tracking the S&P 500 Index. Over the past 10 years, SOKAX returned 6.37%/yr vs 14.89%/yr for SPIIX. Their correlation of 0.86 suggests significant overlap in exposure. SOKAX charges 0.35%/yr vs 0.65%/yr for SPIIX.

Performance

SOKAX vs. SPIIX - Performance Comparison

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

Returns By Period

In the year-to-date period, SOKAX achieves a 7.60% return, which is significantly lower than SPIIX's 11.33% return. Over the past 10 years, SOKAX has underperformed SPIIX with an annualized return of 6.37%, while SPIIX has yielded a comparatively higher 14.89% annualized return.

SOKAX

• 1D: 0.24%
• 1M: 2.63%
• YTD: 7.60%
• 6M: 8.12%
• 1Y: 18.05%
• 3Y*: 12.04%
• 5Y*: 5.06%
• 10Y*: 6.37%

SPIIX

• 1D: 0.12%
• 1M: 5.72%
• YTD: 11.33%
• 6M: 11.21%
• 1Y: 27.96%
• 3Y*: 21.87%
• 5Y*: 13.46%
• 10Y*: 14.89%

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

SOKAX vs. SPIIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
SOKAX SEI Asset Allocation Trust Core Market Strategy Fund	7.60%	15.10%	7.84%	9.50%	-14.65%	8.05%	8.87%	17.14%	-6.24%	11.76%
SPIIX SEI S&P 500 Index Fund Class I	11.33%	16.97%	24.11%	25.49%	-18.84%	28.04%	17.66%	30.72%	-5.00%	21.06%

Correlation

The correlation between SOKAX and SPIIX is 0.85, 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	0.85
Correlation (3Y) Calculated over the trailing 3-year period	0.83
Correlation (5Y) Calculated over the trailing 5-year period	0.82
Correlation (10Y) Calculated over the trailing 10-year period	0.83
Correlation (All Time) Calculated using the full available price history since Nov 19, 2003	0.86

The correlation between SOKAX and SPIIX has been stable across timeframes, ranging from 0.82 to 0.86 - a consistent structural relationship.

Return for Risk

SOKAX vs. SPIIX — Risk / Return Rank

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

SOKAX

SOKAX Risk / Return Rank: 75
SOKAX Sharpe Ratio Rank: 81
SOKAX Sortino Ratio Rank: 79
SOKAX Omega Ratio Rank: 77
SOKAX Calmar Ratio Rank: 67
SOKAX Martin Ratio Rank: 72

SPIIX

SPIIX Risk / Return Rank: 68
SPIIX Sharpe Ratio Rank: 70
SPIIX Sortino Ratio Rank: 62
SPIIX Omega Ratio Rank: 63
SPIIX Calmar Ratio Rank: 69
SPIIX Martin Ratio Rank: 79

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.

SOKAX vs. SPIIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for SEI Asset Allocation Trust Core Market Strategy Fund (SOKAX) 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.

	SOKAX	SPIIX	Difference
Sharpe ratio Return per unit of total volatility	2.66	2.44	+0.22
Sortino ratio Return per unit of downside risk	3.80	3.31	+0.49
Omega ratio Gain probability vs. loss probability	1.51	1.44	+0.06
Calmar ratio Return relative to maximum drawdown	3.18	3.20	-0.02
Martin ratio Return relative to average drawdown	13.66	14.82	-1.15
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

SOKAX vs. SPIIX - Sharpe Ratio Comparison

The current SOKAX Sharpe Ratio is 2.66, which is comparable to the SPIIX Sharpe Ratio of 2.44. The chart below compares the historical Sharpe Ratios of SOKAX and SPIIX, 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

	SOKAX	SPIIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.66	2.44	+0.22
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.56	0.73	-0.17
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.74	0.79	-0.05
Sharpe Ratio (All Time) Calculated using the full available price history	0.67	0.57	+0.10

Drawdowns

SOKAX vs. SPIIX - Drawdown Comparison

The maximum SOKAX drawdown since its inception was -35.64%, smaller than the maximum SPIIX drawdown of -55.78%. Use the drawdown chart below to compare losses from any high point for SOKAX and SPIIX.

Drawdown Indicators

	SOKAX	SPIIX	Difference
Max Drawdown Largest peak-to-trough decline	-35.64%	-55.78%	+20.14%
Max Drawdown (1Y) Largest decline over 1 year	-5.71%	-9.02%	+3.31%
Max Drawdown (3Y) Largest decline over 3 years	-8.02%	-25.70%	+17.68%
Max Drawdown (5Y) Largest decline over 5 years	-23.27%	-25.70%	+2.43%
Max Drawdown (10Y) Largest decline over 10 years	-23.27%	-33.85%	+10.58%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-4.64%	-7.28%	+2.64%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.32%	1.94%	-0.62%

Volatility

SOKAX vs. SPIIX - Volatility Comparison

The current volatility for SEI Asset Allocation Trust Core Market Strategy Fund (SOKAX) is 2.17%, while SEI S&P 500 Index Fund Class I (SPIIX) has a volatility of 2.83%. This indicates that SOKAX 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

	SOKAX	SPIIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.17%	2.83%	-0.66%
Volatility (6M) Calculated over the trailing 6-month period	5.48%	8.94%	-3.46%
Volatility (1Y) Calculated over the trailing 1-year period	6.81%	11.83%	-5.02%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	9.04%	18.44%	-9.40%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	8.58%	18.87%	-10.29%

SOKAX vs. SPIIX - Expense Ratio Comparison

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

Dividends

SOKAX vs. SPIIX - Dividend Comparison

SOKAX's dividend yield for the trailing twelve months is around 2.95%, less than SPIIX's 7.57% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
SOKAX SEI Asset Allocation Trust Core Market Strategy Fund	2.95%	3.06%	2.87%	2.54%	11.01%	10.11%	4.41%	5.25%	4.26%	1.94%	5.80%	3.09%
SPIIX SEI S&P 500 Index Fund Class I	7.57%	8.42%	12.20%	4.10%	10.27%	7.03%	5.78%	4.04%	3.90%	2.08%	4.34%	1.53%

Frequently Asked Questions

Can I hold both SOKAX and SPIIX in my portfolio?

SOKAX and SPIIX have a correlation of 0.85, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, SOKAX or SPIIX?

SPIIX has higher volatility (2.83%) compared to SOKAX (2.17%). In terms of maximum drawdown, SOKAX dropped -35.64% vs SPIIX's -55.78%.

Which has better risk-adjusted returns?

SOKAX currently has the higher Sharpe Ratio (2.66 vs 2.44), 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.