VBIMX vs. VMBSX
VBIMX (Vanguard Intermediate-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, VBIMX returned 1.89%/yr vs 1.85%/yr for VMBSX. Their correlation of 0.83 suggests significant overlap in exposure. VBIMX charges 0.05%/yr vs 0.07%/yr for VMBSX.
Performance
VBIMX vs. VMBSX - Performance Comparison
Loading charts...
Returns By Period
In the year-to-date period, VBIMX achieves a -0.33% return, which is significantly lower than VMBSX's 0.60% return. Both investments have delivered pretty close results over the past 10 years, with VBIMX having a 1.89% annualized return and VMBSX not far behind at 1.85%.
VBIMX
- 1D
- -0.29%
- 1M
- -0.11%
- YTD
- -0.33%
- 6M
- -0.26%
- 1Y
- 4.18%
- 3Y*
- 4.19%
- 5Y*
- 0.18%
- 10Y*
- 1.89%
VMBSX
- 1D
- -0.21%
- 1M
- 0.08%
- YTD
- 0.60%
- 6M
- 0.94%
- 1Y
- 6.11%
- 3Y*
- 4.62%
- 5Y*
- 0.47%
- 10Y*
- 1.85%
VBIMX vs. VMBSX - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
VBIMX Vanguard Intermediate-Term Bond Index Fund Institutional Shares | -0.33% | 8.59% | 1.55% | 5.78% | -13.25% | -2.50% | 9.83% | 10.22% | -0.13% | 3.89% |
VMBSX Vanguard Mortgage-Backed Securities Index Fund Admiral Shares | 0.60% | 8.43% | 1.76% | 4.99% | -11.56% | -1.35% | 3.74% | 11.47% | 0.87% | 2.32% |
Correlation
The correlation between VBIMX and VMBSX is 0.91, 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 | 0.91 |
Correlation (3Y) Calculated over the trailing 3-year period | 0.93 |
Correlation (5Y) Calculated over the trailing 5-year period | 0.92 |
Correlation (10Y) Calculated over the trailing 10-year period | 0.86 |
Correlation (All Time) Calculated using the full available price history since Nov 24, 2009 | 0.83 |
The correlation between VBIMX and VMBSX has been stable across timeframes, ranging from 0.83 to 0.93 - 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
VBIMX vs. VMBSX — Risk / Return Rank
VBIMX
VMBSX
VBIMX vs. VMBSX - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for Vanguard Intermediate-Term Bond Index Fund Institutional Shares (VBIMX) 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.
| VBIMX | VMBSX | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | -0.63 | ||
| Sortino ratioReturn per unit of downside risk | -0.92 | ||
| Omega ratioGain probability vs. loss probability | 1.20 | 1.33 | -0.13 |
| Calmar ratioReturn relative to maximum drawdown | 1.40 | 2.54 | -1.14 |
| Martin ratioReturn relative to average drawdown | 4.22 | 8.52 | -4.29 |
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
| VBIMX | VMBSX | Difference | |
|---|---|---|---|
Sharpe Ratio (1Y)Calculated over the trailing 1-year period | 1.15 | 1.78 | -0.63 |
Sharpe Ratio (5Y)Calculated over the trailing 5-year period | 0.03 | 0.07 | -0.05 |
Sharpe Ratio (10Y)Calculated over the trailing 10-year period | 0.35 | 0.38 | -0.03 |
Sharpe Ratio (All Time)Calculated using the full available price history | 0.67 | 0.58 | +0.09 |
Drawdowns
VBIMX vs. VMBSX - Drawdown Comparison
The maximum VBIMX drawdown since its inception was -19.07%, which is greater than VMBSX's maximum drawdown of -17.44%. Use the drawdown chart below to compare losses from any high point for VBIMX and VMBSX.
Loading charts...
Drawdown Indicators
| VBIMX | VMBSX | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -19.07% | -17.44% | -1.63% |
Max Drawdown (1Y)Largest decline over 1 year | -3.42% | -2.67% | -0.75% |
Max Drawdown (3Y)Largest decline over 3 years | -6.05% | -7.53% | +1.48% |
Max Drawdown (5Y)Largest decline over 5 years | -18.84% | -17.12% | -1.72% |
Max Drawdown (10Y)Largest decline over 10 years | -19.07% | -17.44% | -1.63% |
Current DrawdownCurrent decline from peak | -2.11% | -1.43% | -0.68% |
Average DrawdownAverage peak-to-trough decline | -3.32% | -2.48% | -0.84% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 1.14% | 0.79% | +0.35% |
Volatility
VBIMX vs. VMBSX - Volatility Comparison
Vanguard Intermediate-Term Bond Index Fund Institutional Shares (VBIMX) and Vanguard Mortgage-Backed Securities Index Fund Admiral Shares (VMBSX) have volatilities of 1.41% and 1.43%, 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
| VBIMX | VMBSX | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 1.41% | 1.43% | -0.02% |
Volatility (6M)Calculated over the trailing 6-month period | 3.00% | 2.72% | +0.28% |
Volatility (1Y)Calculated over the trailing 1-year period | 4.19% | 3.82% | +0.37% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 6.39% | 6.40% | -0.01% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 5.38% | 4.86% | +0.52% |
VBIMX vs. VMBSX - Expense Ratio Comparison
VBIMX 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
VBIMX vs. VMBSX - Dividend Comparison
VBIMX's dividend yield for the trailing twelve months is around 4.25%, more than VMBSX's 4.17% yield.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
VBIMX Vanguard Intermediate-Term Bond Index Fund Institutional Shares | 4.25% | 4.03% | 3.82% | 2.82% | 2.41% | 3.23% | 2.95% | 2.75% | 2.89% | 2.76% | 3.08% | 3.12% |
VMBSX Vanguard Mortgage-Backed Securities Index Fund Admiral Shares | 4.17% | 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
With a correlation of 0.91, VBIMX and VMBSX 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.
VMBSX has higher volatility (1.43%) compared to VBIMX (1.41%). In terms of maximum drawdown, VBIMX dropped -19.07% vs VMBSX's -17.44%.
VMBSX currently has the higher Sharpe Ratio (1.78 vs 1.15), 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 VBIMX and VMBSX
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