TAXF vs. AMUN

Last updated Jun 3, 2026

TAXF (American Century Diversified Municipal Bond ETF) and AMUN (abrdn Ultra Short Municipal Income Active ETF) are both Municipal Bonds funds. Both are actively managed. At a 0.30 correlation, their price movements are largely independent. TAXF charges 0.29%/yr vs 0.25%/yr for AMUN.

Performance

TAXF vs. AMUN - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Century Diversified Municipal Bond ETF (TAXF) and abrdn Ultra Short Municipal Income Active ETF (AMUN). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, TAXF achieves a 1.97% return, which is significantly higher than AMUN's 1.13% return.

TAXF

• 1D: 0.19%
• 1M: 0.78%
• YTD: 1.97%
• 6M: 2.33%
• 1Y: 8.33%
• 3Y*: 4.23%
• 5Y*: 1.11%
• 10Y*: —

AMUN

• 1D: 0.08%
• 1M: 0.34%
• YTD: 1.13%
• 6M: 1.40%
• 1Y: —
• 3Y*: —
• 5Y*: —
• 10Y*: —

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

TAXF vs. AMUN - Yearly Performance Comparison

	2026 (YTD)	2025
TAXF American Century Diversified Municipal Bond ETF	1.97%	0.38%
AMUN abrdn Ultra Short Municipal Income Active ETF	1.13%	0.14%

Correlation

The correlation between TAXF and AMUN is 0.30, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (All Time) Calculated using the full available price history since Oct 21, 2025	0.30

Return for Risk

TAXF vs. AMUN — Risk / Return Rank

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

TAXF

TAXF Risk / Return Rank: 74
TAXF Sharpe Ratio Rank: 83
TAXF Sortino Ratio Rank: 87
TAXF Omega Ratio Rank: 90
TAXF Calmar Ratio Rank: 55
TAXF Martin Ratio Rank: 56

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.

TAXF vs. AMUN - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Century Diversified Municipal Bond ETF (TAXF) and abrdn Ultra Short Municipal Income Active ETF (AMUN). 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.

	TAXF	AMUN	Difference
Sharpe ratio Return per unit of total volatility	2.74	—	—
Sortino ratio Return per unit of downside risk	3.97	—	—
Omega ratio Gain probability vs. loss probability	1.59	—	—
Calmar ratio Return relative to maximum drawdown	2.77	—	—
Martin ratio Return relative to average drawdown	10.00	—	—
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

Sharpe Ratios by Period

	TAXF	AMUN	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.74	—	—
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.27	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.62	2.09	-1.47

Drawdowns

TAXF vs. AMUN - Drawdown Comparison

The maximum TAXF drawdown since its inception was -13.93%, which is greater than AMUN's maximum drawdown of -0.61%. Use the drawdown chart below to compare losses from any high point for TAXF and AMUN.

Drawdown Indicators

	TAXF	AMUN	Difference
Max Drawdown Largest peak-to-trough decline	-13.93%	-0.61%	-13.32%
Max Drawdown (1Y) Largest decline over 1 year	-2.93%	—	—
Max Drawdown (3Y) Largest decline over 3 years	-5.53%	—	—
Max Drawdown (5Y) Largest decline over 5 years	-13.93%	—	—
Current Drawdown Current decline from peak	-0.47%	0.00%	-0.47%
Average Drawdown Average peak-to-trough decline	-3.15%	-0.09%	-3.06%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.81%	—	—

Volatility

Volatility by Period

	TAXF	AMUN	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.00%	—	—
Volatility (6M) Calculated over the trailing 6-month period	2.26%	—	—
Volatility (1Y) Calculated over the trailing 1-year period	3.06%	1.01%	+2.05%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	4.20%	1.01%	+3.19%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	4.66%	1.01%	+3.65%

TAXF vs. AMUN - Expense Ratio Comparison

TAXF has a 0.29% expense ratio, which is higher than AMUN's 0.25% expense ratio.

Dividends

TAXF vs. AMUN - Dividend Comparison

TAXF's dividend yield for the trailing twelve months is around 3.47%, more than AMUN's 1.89% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018
AMUN abrdn Ultra Short Municipal Income Active ETF	1.89%	0.66%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
TAXF American Century Diversified Municipal Bond ETF	3.47%	3.68%	3.38%	2.93%	2.05%	1.58%	2.13%	2.64%	0.69%

Frequently Asked Questions

Can I hold both TAXF and AMUN in my portfolio?

TAXF and AMUN have a correlation of 0.30, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which ETF is better, TAXF or AMUN?

On fees, AMUN is cheaper at 0.25% per year. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF is cheaper, TAXF or AMUN?

AMUN is cheaper with a 0.25% expense ratio, compared with 0.29% for TAXF.

Which ETF pays a higher dividend yield, TAXF or AMUN?

TAXF has the higher dividend yield at 3.47%, compared with 1.89% for AMUN.

What is the main difference between TAXF and AMUN?

They also come from different issuers: American Century and abrdn. Their fees differ too: 0.29% for TAXF and 0.25% for AMUN.