MEMUX vs. ATOIX

Last updated Apr 1, 2026

Compare and contrast key facts about Maine Municipal Fund (MEMUX) and abrdn Ultra Short Municipal Income Fund (ATOIX).

MEMUX is managed by IntegrityVikingFunds. It was launched on Dec 4, 1991. ATOIX is managed by Aberdeen. It was launched on Dec 4, 2002.

Performance

MEMUX vs. ATOIX - Performance Comparison

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

MEMUX vs. ATOIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
MEMUX Maine Municipal Fund	-0.46%	2.89%	-0.08%	5.27%	-10.30%	-0.32%	3.06%	4.37%	0.50%	3.15%
ATOIX abrdn Ultra Short Municipal Income Fund	0.35%	3.33%	3.14%	3.27%	0.87%	-0.04%	0.88%	1.40%	1.54%	2.24%

Returns By Period

In the year-to-date period, MEMUX achieves a -0.46% return, which is significantly lower than ATOIX's 0.35% return. Over the past 10 years, MEMUX has underperformed ATOIX with an annualized return of 0.48%, while ATOIX has yielded a comparatively higher 1.73% annualized return.

MEMUX

• 1D: 0.22%
• 1M: -2.31%
• YTD: -0.46%
• 6M: 1.16%
• 1Y: 3.50%
• 3Y*: 1.80%
• 5Y*: -0.58%
• 10Y*: 0.48%

ATOIX

• 1D: 0.00%
• 1M: -0.10%
• YTD: 0.35%
• 6M: 1.37%
• 1Y: 2.95%
• 3Y*: 3.07%
• 5Y*: 2.17%
• 10Y*: 1.73%

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

MEMUX vs. ATOIX - Expense Ratio Comparison

MEMUX has a 0.98% expense ratio, which is higher than ATOIX's 0.44% expense ratio.

MEMUX

Maine Municipal Fund

ATOIX

abrdn Ultra Short Municipal Income Fund

Return for Risk

MEMUX vs. ATOIX — Risk / Return Rank

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

MEMUX

MEMUX Risk / Return Rank: 31
MEMUX Sharpe Ratio Rank: 24
MEMUX Sortino Ratio Rank: 21
MEMUX Omega Ratio Rank: 66
MEMUX Calmar Ratio Rank: 22
MEMUX Martin Ratio Rank: 24

ATOIX

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

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.

MEMUX vs. ATOIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Maine Municipal Fund (MEMUX) and abrdn Ultra Short Municipal Income Fund (ATOIX). 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.

	MEMUX	ATOIX	Difference
Sharpe ratio Return per unit of total volatility	0.64	3.51	-2.87
Sortino ratio Return per unit of downside risk	0.93	18.38	-17.45
Omega ratio Gain probability vs. loss probability	1.25	11.59	-10.34
Calmar ratio Return relative to maximum drawdown	0.67	32.23	-31.56
Martin ratio Return relative to average drawdown	2.55	93.42	-90.87
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

MEMUX vs. ATOIX - Sharpe Ratio Comparison

The current MEMUX Sharpe Ratio is 0.64, which is lower than the ATOIX Sharpe Ratio of 3.51. The chart below compares the historical Sharpe Ratios of MEMUX and ATOIX, 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

	MEMUX	ATOIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.64	3.51	-2.87
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.14	2.69	-2.83
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.13	2.24	-2.11
Sharpe Ratio (All Time) Calculated using the full available price history	0.52	2.45	-1.94

Correlation

The correlation between MEMUX and ATOIX is 0.16, which is considered to be low. This implies their price changes are not closely related. A low correlation is generally favorable for portfolio diversification, as it helps to reduce overall risk by spreading it across multiple assets with different performance patterns.

Dividends

MEMUX vs. ATOIX - Dividend Comparison

MEMUX's dividend yield for the trailing twelve months is around 2.78%, less than ATOIX's 2.90% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MEMUX Maine Municipal Fund	2.78%	3.01%	2.87%	2.35%	1.98%	1.72%	1.81%	2.40%	2.36%	2.45%	2.43%	2.06%
ATOIX abrdn Ultra Short Municipal Income Fund	2.90%	3.27%	3.09%	3.02%	1.07%	0.06%	0.88%	1.39%	1.42%	2.20%	0.61%	0.52%

Drawdowns

MEMUX vs. ATOIX - Drawdown Comparison

The maximum MEMUX drawdown since its inception was -14.47%, which is greater than ATOIX's maximum drawdown of -1.46%. Use the drawdown chart below to compare losses from any high point for MEMUX and ATOIX.

Drawdown Indicators

	MEMUX	ATOIX	Difference
Max Drawdown Largest peak-to-trough decline	-14.47%	-1.46%	-13.01%
Max Drawdown (1Y) Largest decline over 1 year	-6.28%	-0.10%	-6.18%
Max Drawdown (5Y) Largest decline over 5 years	-14.47%	-0.37%	-14.10%
Max Drawdown (10Y) Largest decline over 10 years	-14.47%	-0.43%	-14.04%
Current Drawdown Current decline from peak	-4.04%	-0.10%	-3.94%
Average Drawdown Average peak-to-trough decline	-2.73%	-0.06%	-2.67%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.66%	0.03%	+1.63%

Volatility

MEMUX vs. ATOIX - Volatility Comparison

Maine Municipal Fund (MEMUX) has a higher volatility of 0.94% compared to abrdn Ultra Short Municipal Income Fund (ATOIX) at 0.10%. This indicates that MEMUX's price experiences larger fluctuations and is considered to be riskier than ATOIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MEMUX	ATOIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.94%	0.10%	+0.84%
Volatility (6M) Calculated over the trailing 6-month period	1.54%	0.65%	+0.89%
Volatility (1Y) Calculated over the trailing 1-year period	6.52%	0.92%	+5.60%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	4.21%	0.81%	+3.40%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	3.81%	0.78%	+3.03%