HYMU vs. MFLX

Last updated Apr 2, 2026

Compare and contrast key facts about BlackRock High Yield Muni Income Bond ETF (HYMU) and First Trust Flexible Municipal High Income ETF (MFLX).

HYMU and MFLX are both exchange-traded funds (ETFs), meaning they are traded on stock exchanges and can be bought and sold throughout the day. HYMU is an actively managed fund by BlackRock. It was launched on Mar 16, 2021. MFLX is an actively managed fund by First Trust. It was launched on Sep 27, 2016.

Performance

HYMU vs. MFLX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in BlackRock High Yield Muni Income Bond ETF (HYMU) and First Trust Flexible Municipal High Income ETF (MFLX). The values are adjusted to include any dividend payments, if applicable.

HYMU vs. MFLX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021
HYMU BlackRock High Yield Muni Income Bond ETF	0.29%	2.58%	6.99%	9.67%	-15.96%	6.71%
MFLX First Trust Flexible Municipal High Income ETF	0.22%	3.94%	3.74%	8.98%	-19.94%	8.68%

Returns By Period

In the year-to-date period, HYMU achieves a 0.29% return, which is significantly higher than MFLX's 0.22% return.

HYMU

• 1D: 0.50%
• 1M: -1.14%
• YTD: 0.29%
• 6M: 1.40%
• 1Y: 1.57%
• 3Y*: 5.45%
• 5Y*: 1.45%
• 10Y*: —

MFLX

• 1D: 0.48%
• 1M: -2.06%
• YTD: 0.22%
• 6M: 1.43%
• 1Y: 3.42%
• 3Y*: 4.62%
• 5Y*: 0.10%
• 10Y*: —

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

HYMU vs. MFLX - Expense Ratio Comparison

HYMU has a 0.35% expense ratio, which is lower than MFLX's 0.88% expense ratio.

MFLX

First Trust Flexible Municipal High Income ETF

HYMU

BlackRock High Yield Muni Income Bond ETF

Return for Risk

HYMU vs. MFLX — Risk / Return Rank

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

HYMU

HYMU Risk / Return Rank: 18
HYMU Sharpe Ratio Rank: 16
HYMU Sortino Ratio Rank: 14
HYMU Omega Ratio Rank: 18
HYMU Calmar Ratio Rank: 18
HYMU Martin Ratio Rank: 22

MFLX

MFLX Risk / Return Rank: 23
MFLX Sharpe Ratio Rank: 22
MFLX Sortino Ratio Rank: 20
MFLX Omega Ratio Rank: 26
MFLX Calmar Ratio Rank: 23
MFLX Martin Ratio Rank: 23

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.

HYMU vs. MFLX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for BlackRock High Yield Muni Income Bond ETF (HYMU) and First Trust Flexible Municipal High Income ETF (MFLX). 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.

	HYMU	MFLX	Difference
Sharpe ratio Return per unit of total volatility	0.20	0.39	-0.19
Sortino ratio Return per unit of downside risk	0.30	0.59	-0.29
Omega ratio Gain probability vs. loss probability	1.07	1.12	-0.05
Calmar ratio Return relative to maximum drawdown	0.31	0.58	-0.27
Martin ratio Return relative to average drawdown	1.53	1.74	-0.21
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

HYMU vs. MFLX - Sharpe Ratio Comparison

The current HYMU Sharpe Ratio is 0.20, which is lower than the MFLX Sharpe Ratio of 0.39. The chart below compares the historical Sharpe Ratios of HYMU and MFLX, 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

	HYMU	MFLX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.20	0.39	-0.19
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.21	0.01	+0.20
Sharpe Ratio (All Time) Calculated using the full available price history	0.23	0.16	+0.06

Correlation

The correlation between HYMU and MFLX is 0.28, 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

HYMU vs. MFLX - Dividend Comparison

HYMU's dividend yield for the trailing twelve months is around 4.51%, more than MFLX's 4.14% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016
HYMU BlackRock High Yield Muni Income Bond ETF	4.51%	4.55%	4.35%	4.35%	4.01%	2.97%	0.00%	0.00%	0.00%	0.00%	0.00%
MFLX First Trust Flexible Municipal High Income ETF	4.14%	4.06%	3.81%	3.65%	4.27%	3.69%	3.21%	2.94%	3.74%	3.80%	0.98%

Drawdowns

HYMU vs. MFLX - Drawdown Comparison

The maximum HYMU drawdown since its inception was -22.55%, smaller than the maximum MFLX drawdown of -26.76%. Use the drawdown chart below to compare losses from any high point for HYMU and MFLX.

Drawdown Indicators

	HYMU	MFLX	Difference
Max Drawdown Largest peak-to-trough decline	-22.55%	-26.76%	+4.21%
Max Drawdown (1Y) Largest decline over 1 year	-6.54%	-6.64%	+0.10%
Max Drawdown (5Y) Largest decline over 5 years	-22.55%	-25.88%	+3.33%
Current Drawdown Current decline from peak	-1.39%	-6.67%	+5.28%
Average Drawdown Average peak-to-trough decline	-6.97%	-8.23%	+1.26%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.37%	2.21%	-0.84%

Volatility

HYMU vs. MFLX - Volatility Comparison

The current volatility for BlackRock High Yield Muni Income Bond ETF (HYMU) is 1.29%, while First Trust Flexible Municipal High Income ETF (MFLX) has a volatility of 1.83%. This indicates that HYMU experiences smaller price fluctuations and is considered to be less risky than MFLX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	HYMU	MFLX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.29%	1.83%	-0.54%
Volatility (6M) Calculated over the trailing 6-month period	1.81%	2.45%	-0.64%
Volatility (1Y) Calculated over the trailing 1-year period	7.95%	8.78%	-0.83%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	7.08%	10.36%	-3.28%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	7.05%	11.38%	-4.33%