VBLLX vs. VMBSX
VBLLX (Vanguard Long-Term Bond Index Fund Institutional Shares) and VMBSX (Vanguard Mortgage-Backed Securities Index Fund Admiral Shares) are both Total Bond Market funds from Vanguard. Over the past 10 years, VBLLX returned 0.86%/yr vs 1.87%/yr for VMBSX. A 0.75 correlation means they provide meaningful diversification when combined. VBLLX charges 0.05%/yr vs 0.07%/yr for VMBSX.
Performance
VBLLX vs. VMBSX - Performance Comparison
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Returns By Period
In the year-to-date period, VBLLX achieves a 0.46% return, which is significantly lower than VMBSX's 0.81% return. Over the past 10 years, VBLLX has underperformed VMBSX with an annualized return of 0.86%, while VMBSX has yielded a comparatively higher 1.87% annualized return.
VBLLX
- 1D
- 0.19%
- 1M
- 1.58%
- YTD
- 0.46%
- 6M
- -0.46%
- 1Y
- 7.09%
- 3Y*
- 1.98%
- 5Y*
- -3.19%
- 10Y*
- 0.86%
VMBSX
- 1D
- 0.00%
- 1M
- 0.46%
- YTD
- 0.81%
- 6M
- 0.99%
- 1Y
- 6.98%
- 3Y*
- 4.69%
- 5Y*
- 0.55%
- 10Y*
- 1.87%
VBLLX vs. VMBSX - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
VBLLX Vanguard Long-Term Bond Index Fund Institutional Shares | 0.46% | 6.60% | -4.12% | 7.13% | -27.20% | -3.08% | 16.27% | 19.15% | -4.71% | 10.89% |
VMBSX Vanguard Mortgage-Backed Securities Index Fund Admiral Shares | 0.81% | 8.43% | 1.76% | 4.99% | -11.56% | -1.35% | 3.74% | 11.47% | 0.87% | 2.32% |
Correlation
The correlation between VBLLX and VMBSX is 0.88, indicating a strong positive relationship between their price movements. Combining them offers limited diversification - they tend to fall together during downturns.
| Correlation | |
|---|---|
Correlation (1Y) Calculated over the trailing 1-year period | 0.88 |
Correlation (3Y) Calculated over the trailing 3-year period | 0.89 |
Correlation (5Y) Calculated over the trailing 5-year period | 0.85 |
Correlation (10Y) Calculated over the trailing 10-year period | 0.78 |
Correlation (All Time) Calculated using the full available price history since Nov 24, 2009 | 0.75 |
The correlation between VBLLX and VMBSX shifts across timeframes, from 0.75 (all time) to 0.89 (3 years), reflecting how their relationship changes across market environments.
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Return for Risk
VBLLX vs. VMBSX — Risk / Return Rank
VBLLX
VMBSX
VBLLX vs. VMBSX - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for Vanguard Long-Term Bond Index Fund Institutional Shares (VBLLX) and Vanguard Mortgage-Backed Securities Index Fund Admiral Shares (VMBSX). 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.
| VBLLX | VMBSX | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | -0.98 | ||
| Sortino ratioReturn per unit of downside risk | -1.48 | ||
| Omega ratioGain probability vs. loss probability | 1.15 | 1.34 | -0.19 |
| Calmar ratioReturn relative to maximum drawdown | 1.19 | 2.63 | -1.44 |
| Martin ratioReturn relative to average drawdown | 3.08 | 8.86 | -5.78 |
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
| VBLLX | VMBSX | Difference | |
|---|---|---|---|
Sharpe Ratio (1Y)Calculated over the trailing 1-year period | 0.86 | 1.84 | -0.98 |
Sharpe Ratio (5Y)Calculated over the trailing 5-year period | -0.25 | 0.09 | -0.33 |
Sharpe Ratio (10Y)Calculated over the trailing 10-year period | 0.07 | 0.39 | -0.31 |
Sharpe Ratio (All Time)Calculated using the full available price history | 0.36 | 0.59 | -0.23 |
Drawdowns
VBLLX vs. VMBSX - Drawdown Comparison
The maximum VBLLX drawdown since its inception was -38.42%, which is greater than VMBSX's maximum drawdown of -17.44%. Use the drawdown chart below to compare losses from any high point for VBLLX and VMBSX.
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Drawdown Indicators
| VBLLX | VMBSX | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -38.42% | -17.44% | -20.98% |
Max Drawdown (1Y)Largest decline over 1 year | -5.98% | -2.67% | -3.31% |
Max Drawdown (3Y)Largest decline over 3 years | -14.90% | -7.53% | -7.37% |
Max Drawdown (5Y)Largest decline over 5 years | -36.29% | -17.12% | -19.17% |
Max Drawdown (10Y)Largest decline over 10 years | -38.42% | -17.44% | -20.98% |
Current DrawdownCurrent decline from peak | -24.51% | -1.22% | -23.29% |
Average DrawdownAverage peak-to-trough decline | -9.20% | -2.48% | -6.72% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 2.31% | 0.79% | +1.52% |
Volatility
VBLLX vs. VMBSX - Volatility Comparison
Vanguard Long-Term Bond Index Fund Institutional Shares (VBLLX) has a higher volatility of 2.73% compared to Vanguard Mortgage-Backed Securities Index Fund Admiral Shares (VMBSX) at 1.46%. This indicates that VBLLX's price experiences larger fluctuations and is considered to be riskier than VMBSX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
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Volatility by Period
| VBLLX | VMBSX | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 2.73% | 1.46% | +1.27% |
Volatility (6M)Calculated over the trailing 6-month period | 5.83% | 2.73% | +3.10% |
Volatility (1Y)Calculated over the trailing 1-year period | 8.32% | 3.82% | +4.50% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 12.90% | 6.40% | +6.50% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 11.59% | 4.86% | +6.73% |
VBLLX vs. VMBSX - Expense Ratio Comparison
VBLLX has a 0.05% expense ratio, which is lower than VMBSX's 0.07% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.
Dividends
VBLLX vs. VMBSX - Dividend Comparison
VBLLX's dividend yield for the trailing twelve months is around 4.77%, more than VMBSX's 4.16% yield.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
VBLLX Vanguard Long-Term Bond Index Fund Institutional Shares | 4.77% | 4.66% | 4.64% | 3.75% | 4.16% | 2.89% | 5.84% | 3.62% | 3.82% | 3.69% | 4.19% | 4.98% |
VMBSX Vanguard Mortgage-Backed Securities Index Fund Admiral Shares | 4.16% | 4.18% | 4.24% | 3.28% | 2.31% | 0.99% | 2.00% | 7.48% | 2.72% | 2.16% | 1.98% | 2.01% |
Frequently Asked Questions
VBLLX and VMBSX have a correlation of 0.88, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.
VBLLX has higher volatility (2.73%) compared to VMBSX (1.46%). In terms of maximum drawdown, VBLLX dropped -38.42% vs VMBSX's -17.44%.
VMBSX currently has the higher Sharpe Ratio (1.84 vs 0.86), 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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