PMBS vs. MBB
PMBS (PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund) and MBB (iShares MBS Bond ETF) are both Mortgage Backed Securities funds. PMBS is actively managed, while MBB is passively managed. Over the past year, PMBS returned 6.61% vs 5.79% for MBB. With a 0.96 correlation, they move nearly in lockstep. PMBS charges 0.71%/yr vs 0.06%/yr for MBB.
Performance
PMBS vs. MBB - Performance Comparison
Loading charts...
Returns By Period
In the year-to-date period, PMBS achieves a 0.96% return, which is significantly higher than MBB's 0.82% return.
PMBS
- 1D
- -0.21%
- 1M
- 0.47%
- YTD
- 0.96%
- 6M
- 1.11%
- 1Y
- 6.61%
- 3Y*
- —
- 5Y*
- —
- 10Y*
- —
MBB
- 1D
- 0.10%
- 1M
- 0.63%
- YTD
- 0.82%
- 6M
- 0.92%
- 1Y
- 5.79%
- 3Y*
- 4.35%
- 5Y*
- 0.43%
- 10Y*
- 1.30%
PMBS vs. MBB - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | |
|---|---|---|---|
PMBS PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund | 0.96% | 8.92% | -2.80% |
MBB iShares MBS Bond ETF | 0.82% | 8.38% | -3.40% |
Correlation
The correlation between PMBS and MBB 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 23, 2024 | 0.96 |
The correlation between PMBS and MBB has been stable across timeframes, ranging from 0.96 to 0.97 - a consistent structural relationship.
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
PMBS vs. MBB — Risk / Return Rank
PMBS
MBB
PMBS vs. MBB - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund (PMBS) and iShares MBS Bond ETF (MBB). 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.
Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.
| PMBS | MBB | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | +0.28 | ||
| Sortino ratioReturn per unit of downside risk | +0.41 | ||
| Omega ratioGain probability vs. loss probability | 1.29 | 1.23 | +0.05 |
| Calmar ratioReturn relative to maximum drawdown | 2.24 | 1.98 | +0.26 |
| Martin ratioReturn relative to average drawdown | 7.15 | 6.17 | +0.98 |
Loading charts...
Drawdowns
PMBS vs. MBB - Drawdown Comparison
The maximum PMBS drawdown since its inception was -4.35%, smaller than the maximum MBB drawdown of -17.64%. Use the drawdown chart below to compare losses from any high point for PMBS and MBB.
Loading charts...
Drawdown Indicators
| PMBS | MBB | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -4.35% | -17.64% | +13.29% |
Max Drawdown (1Y)Largest decline over 1 year | -2.97% | -2.94% | -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 | -1.49% | -1.28% | -0.21% |
Average DrawdownAverage peak-to-trough decline | -1.15% | -2.34% | +1.19% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 0.93% | 0.94% | -0.01% |
Volatility
PMBS vs. MBB - Volatility Comparison
PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund (PMBS) and iShares MBS Bond ETF (MBB) have volatilities of 1.28% and 1.27%, 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.
Loading charts...
Volatility by Period
| PMBS | MBB | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 1.28% | 1.27% | +0.01% |
Volatility (6M)Calculated over the trailing 6-month period | 3.21% | 3.32% | -0.11% |
Volatility (1Y)Calculated over the trailing 1-year period | 4.20% | 4.46% | -0.26% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 4.88% | 6.83% | -1.95% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 4.88% | 5.32% | -0.44% |
PMBS vs. MBB - Expense Ratio Comparison
PMBS has a 0.71% expense ratio, which is higher than MBB's 0.06% expense ratio.
Dividends
PMBS vs. MBB - Dividend Comparison
PMBS's dividend yield for the trailing twelve months is around 4.98%, more than MBB's 4.27% 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, PMBS and MBB 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.
PMBS has higher volatility (1.28%) compared to MBB (1.27%). In terms of maximum drawdown, PMBS dropped -4.35% vs MBB's -17.64%.
On 1-year performance, PMBS leads with 6.61% vs 5.79% 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 6.61% return vs 5.79%. 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: PIMCO and iShares. Their fees differ too: 0.71% for PMBS and 0.06% for MBB.
PMBS currently has the higher Sharpe Ratio (1.58 vs 1.31), 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 PMBS and MBB
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