DFABX vs. ATOIX

Last updated Jun 4, 2026

DFABX (DFA Short-Term Selective State Municipal Bond Portfolio) and ATOIX (abrdn Ultra Short Municipal Income Fund) are both Municipal Bonds funds. Over the past 3 years, DFABX returned 2.82%/yr vs 3.08%/yr for ATOIX. At a 0.02 correlation, their price movements are largely independent. DFABX charges 0.25%/yr vs 0.44%/yr for ATOIX.

Performance

DFABX vs. ATOIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in DFA Short-Term Selective State Municipal Bond Portfolio (DFABX) and abrdn Ultra Short Municipal Income Fund (ATOIX). 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 DFABX having a 0.98% return and ATOIX slightly higher at 1.01%.

DFABX

• 1D: 0.00%
• 1M: 0.20%
• YTD: 0.98%
• 6M: 1.10%
• 1Y: 2.66%
• 3Y*: 2.82%
• 5Y*: —
• 10Y*: —

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%

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

DFABX vs. ATOIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022
DFABX DFA Short-Term Selective State Municipal Bond Portfolio	0.98%	2.46%	2.90%	2.87%	0.55%
ATOIX abrdn Ultra Short Municipal Income Fund	1.01%	3.33%	3.14%	3.27%	1.15%

Correlation

The correlation between DFABX and ATOIX is -0.08, meaning there is essentially no relationship between their price movements. Each responds to its own set of market drivers, making them strong candidates for combining in a diversified portfolio.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	-0.08
Correlation (3Y) Calculated over the trailing 3-year period	-0.03
Correlation (All Time) Calculated using the full available price history since Apr 18, 2022	0.02

Return for Risk

DFABX vs. ATOIX — Risk / Return Rank

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

DFABX

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

ATOIX

ATOIX Risk / Return Rank: 99
ATOIX Sharpe Ratio Rank: 96
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.

DFABX vs. ATOIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for DFA Short-Term Selective State Municipal Bond Portfolio (DFABX) 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.

	DFABX	ATOIX	Difference
Sharpe ratio Return per unit of total volatility	4.77	3.50	+1.27
Sortino ratio Return per unit of downside risk	12.57	17.32	-4.75
Omega ratio Gain probability vs. loss probability	6.47	10.98	-4.51
Calmar ratio Return relative to maximum drawdown	24.96	30.48	-5.52
Martin ratio Return relative to average drawdown	107.63	89.66	+17.97
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

DFABX vs. ATOIX - Sharpe Ratio Comparison

The current DFABX Sharpe Ratio is 4.77, which is higher than the ATOIX Sharpe Ratio of 3.50. The chart below compares the historical Sharpe Ratios of DFABX and ATOIX, 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

	DFABX	ATOIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	4.77	3.50	+1.27
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	—	2.80	—
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	2.28	—
Sharpe Ratio (All Time) Calculated using the full available price history	2.48	2.47	+0.01

Drawdowns

DFABX vs. ATOIX - Drawdown Comparison

The maximum DFABX drawdown since its inception was -2.46%, which is greater than ATOIX's maximum drawdown of -1.46%. Use the drawdown chart below to compare losses from any high point for DFABX and ATOIX.

Drawdown Indicators

	DFABX	ATOIX	Difference
Max Drawdown Largest peak-to-trough decline	-2.46%	-1.46%	-1.00%
Max Drawdown (1Y) Largest decline over 1 year	-0.11%	-0.10%	-0.01%
Max Drawdown (3Y) Largest decline over 3 years	-0.60%	-0.10%	-0.50%
Max Drawdown (5Y) Largest decline over 5 years	—	-0.37%	—
Max Drawdown (10Y) Largest decline over 10 years	—	-0.43%	—
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-0.24%	-0.06%	-0.18%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.02%	0.03%	-0.01%

Volatility

DFABX vs. ATOIX - Volatility Comparison

DFA Short-Term Selective State Municipal Bond Portfolio (DFABX) and abrdn Ultra Short Municipal Income Fund (ATOIX) have volatilities of 0.20% and 0.20%, respectively, indicating that both stocks experience similar levels of price fluctuations. This suggests that the risk associated with both stocks, as measured by volatility, is nearly the same. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	DFABX	ATOIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.20%	0.20%	0.00%
Volatility (6M) Calculated over the trailing 6-month period	0.42%	0.61%	-0.19%
Volatility (1Y) Calculated over the trailing 1-year period	0.56%	0.87%	-0.31%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	0.96%	0.83%	+0.13%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	0.96%	0.79%	+0.17%

DFABX vs. ATOIX - Expense Ratio Comparison

DFABX has a 0.25% expense ratio, which is lower than ATOIX's 0.44% expense ratio.

Dividends

DFABX vs. ATOIX - Dividend Comparison

DFABX's dividend yield for the trailing twelve months is around 2.63%, less than ATOIX's 2.98% 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%
DFABX DFA Short-Term Selective State Municipal Bond Portfolio	2.63%	2.33%	2.86%	2.52%	1.25%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both DFABX and ATOIX in my portfolio?

DFABX and ATOIX have a correlation of -0.08, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, DFABX or ATOIX?

ATOIX has higher volatility (0.20%) compared to DFABX (0.20%). In terms of maximum drawdown, DFABX dropped -2.46% vs ATOIX's -1.46%.

Which has better risk-adjusted returns?

DFABX currently has the higher Sharpe Ratio (4.77 vs 3.50), 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.