SISAX vs. SPIIX

Last updated Jun 25, 2026

SISAX (SEI Asset Allocation Trust Tax-Managed Aggressive Strategy Fund) and SPIIX (SEI S&P 500 Index Fund Class I) are both mutual funds - SISAX 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, SISAX returned 11.18%/yr vs 14.86%/yr for SPIIX. With a 0.95 correlation, they move nearly in lockstep. SISAX charges 0.35%/yr vs 0.65%/yr for SPIIX.

Performance

SISAX vs. SPIIX - Performance Comparison

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

Returns By Period

The year-to-date returns for both investments are quite close, with SISAX having a 7.73% return and SPIIX slightly higher at 7.81%. Over the past 10 years, SISAX has underperformed SPIIX with an annualized return of 11.18%, while SPIIX has yielded a comparatively higher 14.86% annualized return.

SISAX

• 1D: -0.88%
• 1M: -0.14%
• YTD: 7.73%
• 6M: 6.72%
• 1Y: 19.69%
• 3Y*: 15.84%
• 5Y*: 8.61%
• 10Y*: 11.18%

SPIIX

• 1D: -1.44%
• 1M: -1.39%
• YTD: 7.81%
• 6M: 6.47%
• 1Y: 21.37%
• 3Y*: 19.94%
• 5Y*: 12.34%
• 10Y*: 14.86%

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

SISAX vs. SPIIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
SISAX SEI Asset Allocation Trust Tax-Managed Aggressive Strategy Fund	7.73%	18.50%	11.92%	16.12%	-14.34%	20.96%	11.25%	24.42%	-8.94%	20.14%
SPIIX SEI S&P 500 Index Fund Class I	7.81%	16.97%	24.11%	25.49%	-18.84%	28.04%	17.66%	30.72%	-5.00%	21.06%

Correlation

The correlation between SISAX and SPIIX is 0.92, 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	0.92
Correlation (3Y) Calculated over the trailing 3-year period	0.89
Correlation (5Y) Calculated over the trailing 5-year period	0.92
Correlation (10Y) Calculated over the trailing 10-year period	0.93
Correlation (All Time) Calculated using the full available price history since Nov 18, 2003	0.95

The correlation between SISAX and SPIIX has been stable across timeframes, ranging from 0.89 to 0.95 - a consistent structural relationship.

Return for Risk

SISAX vs. SPIIX — Risk / Return Rank

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

SISAX

SISAX Risk / Return Rank: 63
SISAX Sharpe Ratio Rank: 64
SISAX Sortino Ratio Rank: 65
SISAX Omega Ratio Rank: 61
SISAX Calmar Ratio Rank: 59
SISAX Martin Ratio Rank: 67

SPIIX

SPIIX Risk / Return Rank: 51
SPIIX Sharpe Ratio Rank: 49
SPIIX Sortino Ratio Rank: 45
SPIIX Omega Ratio Rank: 47
SPIIX Calmar Ratio Rank: 51
SPIIX Martin Ratio Rank: 64

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.

SISAX vs. SPIIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for SEI Asset Allocation Trust Tax-Managed Aggressive Strategy Fund (SISAX) 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.

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.

	SISAX	SPIIX	Difference
Sharpe ratio: Return per unit of total volatility	1.98	1.83	+0.15
Sortino ratio: Return per unit of downside risk	2.83	2.49	+0.33
Omega ratio: Gain probability vs. loss probability	1.36	1.33	+0.03
Calmar ratio: Return relative to maximum drawdown	2.60	2.54	+0.06
Martin ratio: Return relative to average drawdown	11.16	11.32	-0.16

SISAX vs. SPIIX - Sharpe Ratio Comparison

The current SISAX Sharpe Ratio is 1.98, which is comparable to the SPIIX Sharpe Ratio of 1.83. The chart below compares the historical Sharpe Ratios of SISAX 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.

Drawdowns

SISAX vs. SPIIX - Drawdown Comparison

The maximum SISAX drawdown since its inception was -56.25%, roughly equal to the maximum SPIIX drawdown of -55.78%. Use the drawdown chart below to compare losses from any high point for SISAX and SPIIX.

Drawdown Indicators

	SISAX	SPIIX	Difference
Max Drawdown Largest peak-to-trough decline	-56.25%	-55.78%	-0.47%
Max Drawdown (1Y) Largest decline over 1 year	-8.15%	-9.02%	+0.87%
Max Drawdown (3Y) Largest decline over 3 years	-14.97%	-25.70%	+10.73%
Max Drawdown (5Y) Largest decline over 5 years	-23.64%	-25.70%	+2.06%
Max Drawdown (10Y) Largest decline over 10 years	-34.45%	-33.85%	-0.60%
Current Drawdown Current decline from peak	-1.61%	-3.16%	+1.55%
Average Drawdown Average peak-to-trough decline	-7.50%	-7.27%	-0.23%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.89%	2.02%	-0.13%

Volatility

SISAX vs. SPIIX - Volatility Comparison

The current volatility for SEI Asset Allocation Trust Tax-Managed Aggressive Strategy Fund (SISAX) is 3.47%, while SEI S&P 500 Index Fund Class I (SPIIX) has a volatility of 4.89%. This indicates that SISAX 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

	SISAX	SPIIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.47%	4.89%	-1.42%
Volatility (6M) Calculated over the trailing 6-month period	8.46%	9.91%	-1.45%
Volatility (1Y) Calculated over the trailing 1-year period	10.73%	12.56%	-1.83%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	14.03%	18.54%	-4.51%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	15.56%	18.89%	-3.33%

SISAX vs. SPIIX - Expense Ratio Comparison

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

Dividends

SISAX vs. SPIIX - Dividend Comparison

SISAX's dividend yield for the trailing twelve months is around 9.74%, more than SPIIX's 7.81% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
SISAX SEI Asset Allocation Trust Tax-Managed Aggressive Strategy Fund	9.74%	10.37%	5.01%	5.48%	11.49%	3.61%	4.03%	2.76%	5.26%	1.23%	1.29%	1.14%
SPIIX SEI S&P 500 Index Fund Class I	7.81%	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 SISAX and SPIIX in my portfolio?

With a correlation of 0.92, SISAX and SPIIX move almost identically. Holding both adds very little diversification - you're essentially doubling your position in the same market segment. Choosing one is usually more capital-efficient.

Which is riskier, SISAX or SPIIX?

SPIIX has higher volatility (4.89%) compared to SISAX (3.47%). In terms of maximum drawdown, SISAX dropped -56.25% vs SPIIX's -55.78%.

Which has better risk-adjusted returns?

SISAX currently has the higher Sharpe Ratio (1.98 vs 1.83), 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.