CATF vs. MUB
CATF (American Century California Municipal Bond ETF) and MUB (iShares National AMT-Free Muni Bond ETF) are both Municipal Bonds funds. CATF is actively managed, while MUB is passively managed. Over the past year, CATF returned 7.98% vs 6.95% for MUB. Their correlation of 0.82 suggests significant overlap in exposure. CATF charges 0.27%/yr vs 0.07%/yr for MUB.
Performance
CATF vs. MUB - Performance Comparison
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Returns By Period
In the year-to-date period, CATF achieves a 1.92% return, which is significantly higher than MUB's 1.24% return.
CATF
- 1D
- -0.15%
- 1M
- 0.55%
- YTD
- 1.92%
- 6M
- 1.99%
- 1Y
- 7.98%
- 3Y*
- —
- 5Y*
- —
- 10Y*
- —
MUB
- 1D
- -0.08%
- 1M
- 0.56%
- YTD
- 1.24%
- 6M
- 1.74%
- 1Y
- 6.95%
- 3Y*
- 3.43%
- 5Y*
- 0.86%
- 10Y*
- 2.00%
CATF vs. MUB - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | |
|---|---|---|---|
CATF American Century California Municipal Bond ETF | 1.92% | 3.78% | 0.66% |
MUB iShares National AMT-Free Muni Bond ETF | 1.24% | 3.78% | 0.75% |
Correlation
The correlation between CATF and MUB is 0.72, 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 | 0.72 |
Correlation (All Time) Calculated using the full available price history since Jul 19, 2024 | 0.82 |
The correlation between CATF and MUB shifts across timeframes, from 0.72 (1 year) to 0.82 (all time), reflecting how their relationship changes across market environments.
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Return for Risk
CATF vs. MUB — Risk / Return Rank
CATF
MUB
CATF vs. MUB - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for American Century California Municipal Bond ETF (CATF) and iShares National AMT-Free Muni Bond ETF (MUB). 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.
| CATF | MUB | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | +0.16 | ||
| Sortino ratioReturn per unit of downside risk | +0.40 | ||
| Omega ratioGain probability vs. loss probability | 1.54 | 1.50 | +0.04 |
| Calmar ratioReturn relative to maximum drawdown | 2.90 | 2.50 | +0.39 |
| Martin ratioReturn relative to average drawdown | 10.17 | 8.85 | +1.33 |
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month. | |||
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Sharpe Ratios by Period
| CATF | MUB | Difference | |
|---|---|---|---|
Sharpe Ratio (1Y)Calculated over the trailing 1-year period | 2.55 | 2.39 | +0.16 |
Sharpe Ratio (5Y)Calculated over the trailing 5-year period | — | 0.21 | — |
Sharpe Ratio (10Y)Calculated over the trailing 10-year period | — | 0.41 | — |
Sharpe Ratio (All Time)Calculated using the full available price history | 0.79 | 0.58 | +0.21 |
Drawdowns
CATF vs. MUB - Drawdown Comparison
The maximum CATF drawdown since its inception was -4.83%, smaller than the maximum MUB drawdown of -13.68%. Use the drawdown chart below to compare losses from any high point for CATF and MUB.
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Drawdown Indicators
| CATF | MUB | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -4.83% | -13.68% | +8.85% |
Max Drawdown (1Y)Largest decline over 1 year | -2.77% | -2.79% | +0.02% |
Max Drawdown (3Y)Largest decline over 3 years | — | -5.34% | — |
Max Drawdown (5Y)Largest decline over 5 years | — | -11.88% | — |
Max Drawdown (10Y)Largest decline over 10 years | — | -13.68% | — |
Current DrawdownCurrent decline from peak | -0.58% | -0.70% | +0.12% |
Average DrawdownAverage peak-to-trough decline | -1.27% | -2.23% | +0.96% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 0.79% | 0.79% | 0.00% |
Volatility
CATF vs. MUB - Volatility Comparison
American Century California Municipal Bond ETF (CATF) has a higher volatility of 1.06% compared to iShares National AMT-Free Muni Bond ETF (MUB) at 0.97%. This indicates that CATF's price experiences larger fluctuations and is considered to be riskier than MUB based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
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Volatility by Period
| CATF | MUB | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 1.06% | 0.97% | +0.09% |
Volatility (6M)Calculated over the trailing 6-month period | 2.18% | 2.22% | -0.04% |
Volatility (1Y)Calculated over the trailing 1-year period | 3.14% | 2.92% | +0.22% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 4.33% | 4.06% | +0.27% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 4.33% | 4.92% | -0.59% |
CATF vs. MUB - Expense Ratio Comparison
CATF has a 0.27% expense ratio, which is higher than MUB's 0.07% expense ratio. However, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.
Dividends
CATF vs. MUB - Dividend Comparison
CATF's dividend yield for the trailing twelve months is around 3.22%, more than MUB's 3.17% yield.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
CATF American Century California Municipal Bond ETF | 3.22% | 3.40% | 1.32% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% |
MUB iShares National AMT-Free Muni Bond ETF | 3.17% | 3.14% | 3.01% | 2.65% | 2.11% | 1.81% | 2.11% | 2.42% | 2.46% | 2.26% | 2.21% | 2.51% |
Frequently Asked Questions
CATF and MUB have a correlation of 0.72, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.
CATF has higher volatility (1.06%) compared to MUB (0.97%). In terms of maximum drawdown, CATF dropped -4.83% vs MUB's -13.68%.
On 1-year performance, CATF leads with 7.98% vs 6.95% for MUB. On fees, MUB is cheaper at 0.07% per year. Their volatility is very similar. The better choice depends on whether you care most about return, fees, risk, or income.
Over the 1-year period, CATF has performed better with a 7.98% return vs 6.95%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.
MUB is cheaper with a 0.07% expense ratio, compared with 0.27% for CATF.
CATF has the higher dividend yield at 3.22%, compared with 3.17% for MUB.
They also come from different issuers: American Century and iShares. Their fees differ too: 0.27% for CATF and 0.07% for MUB.
CATF currently has the higher Sharpe Ratio (2.55 vs 2.39), 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.
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