MFLX vs. SMMU
MFLX (First Trust Flexible Municipal High Income ETF) and SMMU (PIMCO Short Term Municipal Bond Active ETF) are both Municipal Bonds funds. Both are actively managed. Over the past 5 years, MFLX returned -0.03%/yr vs 1.90%/yr for SMMU. At a 0.20 correlation, their price movements are largely independent. MFLX charges 0.88%/yr vs 0.35%/yr for SMMU.
Performance
MFLX vs. SMMU - Performance Comparison
Loading charts...
Returns By Period
In the year-to-date period, MFLX achieves a 3.33% return, which is significantly higher than SMMU's 1.10% return.
MFLX
- 1D
- -0.06%
- 1M
- 1.21%
- YTD
- 3.33%
- 6M
- 3.84%
- 1Y
- 9.22%
- 3Y*
- 5.48%
- 5Y*
- -0.03%
- 10Y*
- —
SMMU
- 1D
- 0.07%
- 1M
- 0.31%
- YTD
- 1.10%
- 6M
- 1.36%
- 1Y
- 3.92%
- 3Y*
- 3.67%
- 5Y*
- 1.90%
- 10Y*
- 1.82%
MFLX vs. SMMU - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
MFLX First Trust Flexible Municipal High Income ETF | 3.33% | 3.94% | 3.74% | 8.98% | -19.94% | 8.43% | 7.19% | 16.89% | -4.66% | 5.57% |
SMMU PIMCO Short Term Municipal Bond Active ETF | 1.10% | 4.06% | 2.68% | 4.39% | -2.45% | 0.17% | 2.87% | 3.47% | 1.51% | 2.34% |
Correlation
The correlation between MFLX and SMMU is 0.53, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.
| Correlation | |
|---|---|
Correlation (1Y) Calculated over the trailing 1-year period | 0.53 |
Correlation (3Y) Calculated over the trailing 3-year period | 0.34 |
Correlation (5Y) Calculated over the trailing 5-year period | 0.29 |
Correlation (All Time) Calculated using the full available price history since Sep 30, 2016 | 0.20 |
Over the past year, MFLX and SMMU have become more correlated (0.53) than their long-term average of 0.20, meaning their price movements have been converging.
Compare stocks, funds, or ETFs
Search for stocks, ETFs, and funds for a quick comparison or use the comparison tool for more options.
Return for Risk
MFLX vs. SMMU — Risk / Return Rank
MFLX
SMMU
MFLX vs. SMMU - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for First Trust Flexible Municipal High Income ETF (MFLX) and PIMCO Short Term Municipal Bond Active ETF (SMMU). 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.
| MFLX | SMMU | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | -1.57 | ||
| Sortino ratioReturn per unit of downside risk | -2.35 | ||
| Omega ratioGain probability vs. loss probability | 1.49 | 1.90 | -0.41 |
| Calmar ratioReturn relative to maximum drawdown | 2.97 | 5.10 | -2.13 |
| Martin ratioReturn relative to average drawdown | 11.95 | 18.24 | -6.30 |
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month. | |||
Loading charts...
Sharpe Ratios by Period
| MFLX | SMMU | Difference | |
|---|---|---|---|
Sharpe Ratio (1Y)Calculated over the trailing 1-year period | 2.27 | 3.84 | -1.57 |
Sharpe Ratio (5Y)Calculated over the trailing 5-year period | -0.00 | 1.14 | -1.14 |
Sharpe Ratio (10Y)Calculated over the trailing 10-year period | — | 0.67 | — |
Sharpe Ratio (All Time)Calculated using the full available price history | 0.19 | 0.60 | -0.41 |
Drawdowns
MFLX vs. SMMU - Drawdown Comparison
The maximum MFLX drawdown since its inception was -26.76%, which is greater than SMMU's maximum drawdown of -5.09%. Use the drawdown chart below to compare losses from any high point for MFLX and SMMU.
Loading charts...
Drawdown Indicators
| MFLX | SMMU | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -26.76% | -5.09% | -21.67% |
Max Drawdown (1Y)Largest decline over 1 year | -3.11% | -0.77% | -2.34% |
Max Drawdown (3Y)Largest decline over 3 years | -8.18% | -1.95% | -6.23% |
Max Drawdown (5Y)Largest decline over 5 years | -25.88% | -4.76% | -21.12% |
Max Drawdown (10Y)Largest decline over 10 years | — | -5.09% | — |
Current DrawdownCurrent decline from peak | -3.78% | -0.03% | -3.75% |
Average DrawdownAverage peak-to-trough decline | -8.17% | -0.55% | -7.62% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 0.77% | 0.22% | +0.55% |
Volatility
MFLX vs. SMMU - Volatility Comparison
First Trust Flexible Municipal High Income ETF (MFLX) has a higher volatility of 1.41% compared to PIMCO Short Term Municipal Bond Active ETF (SMMU) at 0.31%. This indicates that MFLX's price experiences larger fluctuations and is considered to be riskier than SMMU based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
Loading charts...
Volatility by Period
| MFLX | SMMU | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 1.41% | 0.31% | +1.10% |
Volatility (6M)Calculated over the trailing 6-month period | 2.98% | 0.79% | +2.19% |
Volatility (1Y)Calculated over the trailing 1-year period | 4.08% | 1.02% | +3.06% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 10.36% | 1.67% | +8.69% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 11.29% | 2.73% | +8.56% |
MFLX vs. SMMU - Expense Ratio Comparison
MFLX has a 0.88% expense ratio, which is higher than SMMU's 0.35% expense ratio.
Dividends
MFLX vs. SMMU - Dividend Comparison
MFLX's dividend yield for the trailing twelve months is around 4.08%, more than SMMU's 2.84% yield.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
MFLX First Trust Flexible Municipal High Income ETF | 4.08% | 4.06% | 3.81% | 3.65% | 4.27% | 3.69% | 3.21% | 2.94% | 3.74% | 3.80% | 0.98% | 0.00% |
SMMU PIMCO Short Term Municipal Bond Active ETF | 2.84% | 2.80% | 3.03% | 2.79% | 1.37% | 0.60% | 1.19% | 1.82% | 1.57% | 1.41% | 1.03% | 0.89% |
Frequently Asked Questions
MFLX and SMMU have a correlation of 0.53, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.
MFLX has higher volatility (1.41%) compared to SMMU (0.31%). In terms of maximum drawdown, MFLX dropped -26.76% vs SMMU's -5.09%.
On 5-year performance, SMMU leads with 1.90% vs -0.03% for MFLX. On fees, SMMU is cheaper at 0.35% per year. On volatility, SMMU has been the lower-risk option at 0.31%. The better choice depends on whether you care most about return, fees, risk, or income.
Over the 5-year period, SMMU has performed better with a 1.90% return vs -0.03%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.
SMMU is cheaper with a 0.35% expense ratio, compared with 0.88% for MFLX.
MFLX has the higher dividend yield at 4.08%, compared with 2.84% for SMMU.
They also come from different issuers: First Trust and PIMCO. Their fees differ too: 0.88% for MFLX and 0.35% for SMMU.
SMMU currently has the higher Sharpe Ratio (3.84 vs 2.27), 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.
Find the right allocation for MFLX and SMMU
Add both to a portfolio and optimize allocations for your target — whether that's maximizing returns, minimizing drawdowns, or balancing risk across holdings.
Open Portfolio Optimizer