MBB vs. PMBS
MBB (iShares MBS Bond ETF) and PMBS (PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund) are both Mortgage Backed Securities funds. MBB is passively managed, while PMBS is actively managed. Over the past year, MBB returned 6.17% vs 7.05% for PMBS. With a 0.96 correlation, they move nearly in lockstep. MBB charges 0.06%/yr vs 0.71%/yr for PMBS.
Performance
MBB vs. PMBS - Performance Comparison
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Returns By Period
In the year-to-date period, MBB achieves a 0.68% return, which is significantly lower than PMBS's 1.03% return.
MBB
- 1D
- 0.11%
- 1M
- 0.25%
- YTD
- 0.68%
- 6M
- 1.10%
- 1Y
- 6.17%
- 3Y*
- 4.42%
- 5Y*
- 0.36%
- 10Y*
- 1.31%
PMBS
- 1D
- 0.13%
- 1M
- 0.14%
- YTD
- 1.03%
- 6M
- 1.52%
- 1Y
- 7.05%
- 3Y*
- —
- 5Y*
- —
- 10Y*
- —
MBB vs. PMBS - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | |
|---|---|---|---|
MBB iShares MBS Bond ETF | 0.68% | 8.38% | -3.33% |
PMBS PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund | 1.03% | 8.92% | -2.75% |
Correlation
The correlation between MBB and PMBS is 0.97 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.
| Correlation | |
|---|---|
Correlation (1Y) Calculated over the trailing 1-year period | 0.97 |
Correlation (All Time) Calculated using the full available price history since Sep 24, 2024 | 0.96 |
The correlation between MBB and PMBS has been stable across timeframes, ranging from 0.96 to 0.97 - a consistent structural relationship.
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Return for Risk
MBB vs. PMBS — Risk / Return Rank
MBB
PMBS
MBB vs. PMBS - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for iShares MBS Bond ETF (MBB) and PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund (PMBS). 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.
| MBB | PMBS | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | -0.30 | ||
| Sortino ratioReturn per unit of downside risk | -0.46 | ||
| Omega ratioGain probability vs. loss probability | 1.25 | 1.31 | -0.06 |
| Calmar ratioReturn relative to maximum drawdown | 2.10 | 2.39 | -0.28 |
| Martin ratioReturn relative to average drawdown | 6.96 | 8.09 | -1.13 |
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
| MBB | PMBS | Difference | |
|---|---|---|---|
Sharpe Ratio (1Y)Calculated over the trailing 1-year period | 1.39 | 1.69 | -0.30 |
Sharpe Ratio (5Y)Calculated over the trailing 5-year period | 0.05 | — | — |
Sharpe Ratio (10Y)Calculated over the trailing 10-year period | 0.25 | — | — |
Sharpe Ratio (All Time)Calculated using the full available price history | 0.59 | 0.84 | -0.26 |
Drawdowns
MBB vs. PMBS - Drawdown Comparison
The maximum MBB drawdown since its inception was -17.64%, which is greater than PMBS's maximum drawdown of -4.35%. Use the drawdown chart below to compare losses from any high point for MBB and PMBS.
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Drawdown Indicators
| MBB | PMBS | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -17.64% | -4.35% | -13.29% |
Max Drawdown (1Y)Largest decline over 1 year | -2.94% | -2.97% | +0.03% |
Max Drawdown (3Y)Largest decline over 3 years | -7.68% | — | — |
Max Drawdown (5Y)Largest decline over 5 years | -17.19% | — | — |
Max Drawdown (10Y)Largest decline over 10 years | -17.64% | — | — |
Current DrawdownCurrent decline from peak | -1.42% | -1.42% | 0.00% |
Average DrawdownAverage peak-to-trough decline | -2.35% | -1.15% | -1.20% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 0.89% | 0.87% | +0.02% |
Volatility
MBB vs. PMBS - Volatility Comparison
iShares MBS Bond ETF (MBB) and PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund (PMBS) have volatilities of 1.58% and 1.53%, 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.
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Volatility by Period
| MBB | PMBS | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 1.58% | 1.53% | +0.05% |
Volatility (6M)Calculated over the trailing 6-month period | 3.23% | 3.09% | +0.14% |
Volatility (1Y)Calculated over the trailing 1-year period | 4.51% | 4.22% | +0.29% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 6.81% | 4.87% | +1.94% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 5.31% | 4.87% | +0.44% |
MBB vs. PMBS - Expense Ratio Comparison
MBB has a 0.06% expense ratio, which is lower than PMBS's 0.71% expense ratio.
Dividends
MBB vs. PMBS - Dividend Comparison
MBB's dividend yield for the trailing twelve months is around 4.27%, less than PMBS's 4.98% yield.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
MBB iShares MBS Bond ETF | 4.27% | 4.21% | 3.94% | 3.40% | 2.31% | 1.05% | 2.10% | 2.77% | 2.64% | 2.23% | 2.58% | 2.66% |
PMBS PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund | 4.98% | 4.73% | 1.59% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% |
Frequently Asked Questions
With a correlation of 0.97, MBB and PMBS move almost identically. Holding both adds very little diversification - you're essentially doubling your position in the same market segment. Choosing one is usually more capital-efficient.
MBB has higher volatility (1.58%) compared to PMBS (1.53%). In terms of maximum drawdown, MBB dropped -17.64% vs PMBS's -4.35%.
On 1-year performance, PMBS leads with 7.05% vs 6.17% for MBB. On fees, MBB is cheaper at 0.06% 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, PMBS has performed better with a 7.05% return vs 6.17%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.
MBB is cheaper with a 0.06% expense ratio, compared with 0.71% for PMBS.
PMBS has the higher dividend yield at 4.98%, compared with 4.27% for MBB.
They also come from different issuers: iShares and PIMCO. Their fees differ too: 0.06% for MBB and 0.71% for PMBS.
PMBS currently has the higher Sharpe Ratio (1.69 vs 1.39), 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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