ATOIX vs. SUMAX

Last updated Jun 24, 2026

ATOIX (abrdn Ultra Short Municipal Income Fund) and SUMAX (SEI Tax Exempt Trust Short Duration Municipal Fund) are both Municipal Bonds funds. Over the past 10 years, ATOIX returned 1.79%/yr vs 1.42%/yr for SUMAX. At a 0.22 correlation, their price movements are largely independent. ATOIX charges 0.44%/yr vs 0.63%/yr for SUMAX.

Performance

ATOIX vs. SUMAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in abrdn Ultra Short Municipal Income Fund (ATOIX) and SEI Tax Exempt Trust Short Duration Municipal Fund (SUMAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, ATOIX achieves a 1.01% return, which is significantly higher than SUMAX's 0.90% return. Over the past 10 years, ATOIX has outperformed SUMAX with an annualized return of 1.79%, while SUMAX has yielded a comparatively lower 1.42% annualized return.

ATOIX

• 1D: 0.00%
• 1M: 0.20%
• YTD: 1.01%
• 6M: 1.54%
• 1Y: 3.02%
• 3Y*: 3.08%
• 5Y*: 2.30%
• 10Y*: 1.79%

SUMAX

• 1D: 0.00%
• 1M: 0.43%
• YTD: 0.90%
• 6M: 1.23%
• 1Y: 2.96%
• 3Y*: 3.26%
• 5Y*: 1.72%
• 10Y*: 1.42%

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

ATOIX vs. SUMAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
ATOIX abrdn Ultra Short Municipal Income Fund	1.01%	3.33%	3.14%	3.27%	0.87%	-0.04%	0.88%	1.40%	1.54%	2.24%
SUMAX SEI Tax Exempt Trust Short Duration Municipal Fund	0.90%	4.38%	2.49%	3.22%	-2.08%	-0.01%	1.77%	2.28%	1.09%	0.88%

Correlation

The correlation between ATOIX and SUMAX is 0.28, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.28
Correlation (3Y) Calculated over the trailing 3-year period	0.33
Correlation (5Y) Calculated over the trailing 5-year period	0.31
Correlation (10Y) Calculated over the trailing 10-year period	0.34
Correlation (All Time) Calculated using the full available price history since Dec 16, 2003	0.22

The correlation between ATOIX and SUMAX shifts across timeframes, from 0.22 (all time) to 0.34 (10 years), reflecting how their relationship changes across market environments.

Return for Risk

ATOIX vs. SUMAX — Risk / Return Rank

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

ATOIX

ATOIX Risk / Return Rank: 99
ATOIX Sharpe Ratio Rank: 98
ATOIX Sortino Ratio Rank: 100
ATOIX Omega Ratio Rank: 100
ATOIX Calmar Ratio Rank: 100
ATOIX Martin Ratio Rank: 100

SUMAX

SUMAX Risk / Return Rank: 90
SUMAX Sharpe Ratio Rank: 89
SUMAX Sortino Ratio Rank: 98
SUMAX Omega Ratio Rank: 98
SUMAX Calmar Ratio Rank: 85
SUMAX 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.

ATOIX vs. SUMAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for abrdn Ultra Short Municipal Income Fund (ATOIX) and SEI Tax Exempt Trust Short Duration Municipal Fund (SUMAX). 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.

	ATOIX	SUMAX	Difference
Sharpe ratio: Return per unit of total volatility	3.50	2.71	+0.78
Sortino ratio: Return per unit of downside risk	17.32	5.75	+11.57
Omega ratio: Gain probability vs. loss probability	10.98	2.17	+8.81
Calmar ratio: Return relative to maximum drawdown	30.48	3.88	+26.60
Martin ratio: Return relative to average drawdown	89.66	13.80	+75.86

ATOIX vs. SUMAX - Sharpe Ratio Comparison

The current ATOIX Sharpe Ratio is 3.50, which is comparable to the SUMAX Sharpe Ratio of 2.71. The chart below compares the historical Sharpe Ratios of ATOIX and SUMAX, 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

ATOIX vs. SUMAX - Drawdown Comparison

The maximum ATOIX drawdown since its inception was -1.46%, smaller than the maximum SUMAX drawdown of -3.70%. Use the drawdown chart below to compare losses from any high point for ATOIX and SUMAX.

Drawdown Indicators

	ATOIX	SUMAX	Difference
Max Drawdown Largest peak-to-trough decline	-1.46%	-3.70%	+2.24%
Max Drawdown (1Y) Largest decline over 1 year	-0.10%	-0.79%	+0.69%
Max Drawdown (3Y) Largest decline over 3 years	-0.10%	-1.40%	+1.30%
Max Drawdown (5Y) Largest decline over 5 years	-0.37%	-3.70%	+3.33%
Max Drawdown (10Y) Largest decline over 10 years	-0.43%	-3.70%	+3.27%
Current Drawdown Current decline from peak	0.00%	-0.10%	+0.10%
Average Drawdown Average peak-to-trough decline	-0.06%	-0.26%	+0.20%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.03%	0.22%	-0.19%

Volatility

ATOIX vs. SUMAX - Volatility Comparison

The current volatility for abrdn Ultra Short Municipal Income Fund (ATOIX) is 0.20%, while SEI Tax Exempt Trust Short Duration Municipal Fund (SUMAX) has a volatility of 0.33%. This indicates that ATOIX experiences smaller price fluctuations and is considered to be less risky than SUMAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	ATOIX	SUMAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.20%	0.33%	-0.13%
Volatility (6M) Calculated over the trailing 6-month period	0.61%	0.86%	-0.25%
Volatility (1Y) Calculated over the trailing 1-year period	0.87%	1.13%	-0.26%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	0.83%	1.39%	-0.56%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	0.79%	1.23%	-0.44%

ATOIX vs. SUMAX - Expense Ratio Comparison

ATOIX has a 0.44% expense ratio, which is lower than SUMAX's 0.63% expense ratio.

Dividends

ATOIX vs. SUMAX - Dividend Comparison

ATOIX's dividend yield for the trailing twelve months is around 2.98%, more than SUMAX's 2.72% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
ATOIX abrdn Ultra Short Municipal Income Fund	2.98%	3.27%	3.09%	3.02%	1.07%	0.06%	0.88%	1.39%	1.42%	2.20%	0.61%	0.52%
SUMAX SEI Tax Exempt Trust Short Duration Municipal Fund	2.72%	3.37%	2.36%	1.73%	0.71%	0.58%	1.06%	1.45%	1.08%	0.67%	0.39%	0.79%

Frequently Asked Questions

Can I hold both ATOIX and SUMAX in my portfolio?

ATOIX and SUMAX have a correlation of 0.28, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, ATOIX or SUMAX?

SUMAX has higher volatility (0.33%) compared to ATOIX (0.20%). In terms of maximum drawdown, ATOIX dropped -1.46% vs SUMAX's -3.70%.

Which has better risk-adjusted returns?

ATOIX currently has the higher Sharpe Ratio (3.50 vs 2.71), 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.