VMBIX vs. VUBFX
Compare and contrast key facts about Vanguard Mortgage-Backed Securities Index Fund Institutional Shares (VMBIX) and Vanguard Ultra-Short-Term Bond Fund Investor Shares (VUBFX).
VMBIX is managed by Vanguard. It was launched on Oct 31, 2013. VUBFX is managed by Vanguard. It was launched on Feb 24, 2015.
Performance
VMBIX vs. VUBFX - Performance Comparison
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VMBIX vs. VUBFX - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
VMBIX Vanguard Mortgage-Backed Securities Index Fund Institutional Shares | 0.45% | 8.44% | 1.78% | 4.97% | -11.56% | -1.30% | 3.77% | 6.19% | 0.88% | 2.38% |
VUBFX Vanguard Ultra-Short-Term Bond Fund Investor Shares | 0.59% | 5.04% | 5.99% | 5.43% | -0.53% | 0.03% | 1.95% | 3.34% | 1.94% | 1.23% |
Returns By Period
In the year-to-date period, VMBIX achieves a 0.45% return, which is significantly lower than VUBFX's 0.59% return. Over the past 10 years, VMBIX has underperformed VUBFX with an annualized return of 1.41%, while VUBFX has yielded a comparatively higher 2.56% annualized return.
VMBIX
- 1D
- 0.20%
- 1M
- -1.13%
- YTD
- 0.45%
- 6M
- 1.79%
- 1Y
- 5.39%
- 3Y*
- 4.35%
- 5Y*
- 0.51%
- 10Y*
- 1.41%
VUBFX
- 1D
- 0.00%
- 1M
- -0.10%
- YTD
- 0.59%
- 6M
- 1.62%
- 1Y
- 4.31%
- 3Y*
- 5.24%
- 5Y*
- 3.26%
- 10Y*
- 2.56%
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VMBIX vs. VUBFX - Expense Ratio Comparison
VMBIX has a 0.05% expense ratio, which is lower than VUBFX's 0.20% 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%.
Return for Risk
VMBIX vs. VUBFX — Risk / Return Rank
VMBIX
VUBFX
VMBIX vs. VUBFX - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for Vanguard Mortgage-Backed Securities Index Fund Institutional Shares (VMBIX) and Vanguard Ultra-Short-Term Bond Fund Investor Shares (VUBFX). 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.
| VMBIX | VUBFX | Difference | |
|---|---|---|---|
Sharpe ratioReturn per unit of total volatility | 1.33 | 5.18 | -3.84 |
Sortino ratioReturn per unit of downside risk | 1.92 | 10.17 | -8.25 |
Omega ratioGain probability vs. loss probability | 1.24 | 3.60 | -2.36 |
Calmar ratioReturn relative to maximum drawdown | 2.27 | 14.46 | -12.19 |
Martin ratioReturn relative to average drawdown | 6.41 | 65.22 | -58.81 |
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
| VMBIX | VUBFX | Difference | |
|---|---|---|---|
Sharpe Ratio (1Y)Calculated over the trailing 1-year period | 1.33 | 5.18 | -3.84 |
Sharpe Ratio (5Y)Calculated over the trailing 5-year period | 0.08 | 3.34 | -3.26 |
Sharpe Ratio (10Y)Calculated over the trailing 10-year period | 0.30 | 3.07 | -2.77 |
Sharpe Ratio (All Time)Calculated using the full available price history | 0.51 | 3.06 | -2.55 |
Correlation
The correlation between VMBIX and VUBFX is 0.40, which is considered to be moderate. This suggests that the two assets have some degree of positive relationship in their price movements. Moderate correlation can be acceptable for portfolio diversification, offering a balance between risk and potential returns.
Dividends
VMBIX vs. VUBFX - Dividend Comparison
VMBIX's dividend yield for the trailing twelve months is around 3.88%, less than VUBFX's 4.12% yield.
| TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
VMBIX Vanguard Mortgage-Backed Securities Index Fund Institutional Shares | 3.88% | 4.20% | 4.27% | 3.29% | 2.33% | 1.01% | 2.02% | 2.76% | 2.74% | 2.18% | 2.13% | 2.04% |
VUBFX Vanguard Ultra-Short-Term Bond Fund Investor Shares | 4.12% | 4.62% | 5.42% | 4.06% | 1.28% | 0.43% | 1.52% | 2.58% | 2.13% | 1.43% | 0.98% | 0.00% |
Drawdowns
VMBIX vs. VUBFX - Drawdown Comparison
The maximum VMBIX drawdown since its inception was -17.44%, which is greater than VUBFX's maximum drawdown of -1.86%. Use the drawdown chart below to compare losses from any high point for VMBIX and VUBFX.
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Drawdown Indicators
| VMBIX | VUBFX | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -17.44% | -1.86% | -15.58% |
Max Drawdown (1Y)Largest decline over 1 year | -2.58% | -0.30% | -2.28% |
Max Drawdown (5Y)Largest decline over 5 years | -17.11% | -1.86% | -15.25% |
Max Drawdown (10Y)Largest decline over 10 years | -17.44% | -1.86% | -15.58% |
Current DrawdownCurrent decline from peak | -1.56% | -0.10% | -1.46% |
Average DrawdownAverage peak-to-trough decline | -2.52% | -0.17% | -2.35% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 0.91% | 0.07% | +0.84% |
Volatility
VMBIX vs. VUBFX - Volatility Comparison
Vanguard Mortgage-Backed Securities Index Fund Institutional Shares (VMBIX) has a higher volatility of 1.67% compared to Vanguard Ultra-Short-Term Bond Fund Investor Shares (VUBFX) at 0.34%. This indicates that VMBIX's price experiences larger fluctuations and is considered to be riskier than VUBFX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
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Volatility by Period
| VMBIX | VUBFX | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 1.67% | 0.34% | +1.33% |
Volatility (6M)Calculated over the trailing 6-month period | 2.48% | 0.55% | +1.93% |
Volatility (1Y)Calculated over the trailing 1-year period | 4.29% | 0.84% | +3.45% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 6.33% | 0.98% | +5.35% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 4.76% | 0.84% | +3.92% |