VSTBX vs. PBBBX
VSTBX (Vanguard Short-Term Corporate Bond Index Fund Institutional Shares) and PBBBX (PIA BBB Bond Fund) are both Corporate Bonds funds. Over the past 10 years, VSTBX returned 2.96%/yr vs 2.56%/yr for PBBBX. A 0.78 correlation means they provide meaningful diversification when combined. VSTBX charges 0.05%/yr vs 0.15%/yr for PBBBX.
Performance
VSTBX vs. PBBBX - Performance Comparison
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Returns By Period
In the year-to-date period, VSTBX achieves a 0.91% return, which is significantly higher than PBBBX's 0.12% return. Over the past 10 years, VSTBX has outperformed PBBBX with an annualized return of 2.96%, while PBBBX has yielded a comparatively lower 2.56% annualized return.
VSTBX
- 1D
- 0.08%
- 1M
- 0.14%
- 6M
- 0.87%
- YTD
- 0.91%
- 1Y
- 4.07%
- 3Y*
- 5.80%
- 5Y*
- 2.43%
- 10Y*
- 2.96%
PBBBX
- 1D
- 0.23%
- 1M
- -0.24%
- 6M
- 0.01%
- YTD
- 0.12%
- 1Y
- 4.56%
- 3Y*
- 5.76%
- 5Y*
- 0.19%
- 10Y*
- 2.56%
VSTBX vs. PBBBX - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
VSTBX Vanguard Short-Term Corporate Bond Index Fund Institutional Shares | 0.91% | 6.75% | 5.37% | 6.17% | -5.73% | -0.41% | 5.07% | 9.68% | 0.92% | 2.48% |
PBBBX PIA BBB Bond Fund | 0.12% | 8.14% | 2.41% | 9.19% | -16.35% | -1.20% | 9.37% | 16.49% | -3.02% | 7.16% |
Correlation
The correlation between VSTBX and PBBBX is 0.78, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.
| Correlation | |
|---|---|
Correlation (1Y) Calculated over the trailing 1-year period | 0.78 |
Correlation (3Y) Calculated over the trailing 3-year period | 0.84 |
Correlation (5Y) Calculated over the trailing 5-year period | 0.84 |
Correlation (10Y) Calculated over the trailing 10-year period | 0.79 |
Correlation (All Time) Calculated using the full available price history since Nov 19, 2009 | 0.78 |
The correlation between VSTBX and PBBBX has been stable across timeframes, ranging from 0.78 to 0.84 - a consistent structural relationship.
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Return for Risk
VSTBX vs. PBBBX — Risk / Return Rank
VSTBX
PBBBX
VSTBX vs. PBBBX - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for Vanguard Short-Term Corporate Bond Index Fund Institutional Shares (VSTBX) and PIA BBB Bond Fund (PBBBX). 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.
| VSTBX | PBBBX | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | +1.21 | ||
| Sortino ratioReturn per unit of downside risk | +1.87 | ||
| Omega ratioGain probability vs. loss probability | 1.44 | 1.18 | +0.25 |
| Calmar ratioReturn relative to maximum drawdown | 3.02 | 1.27 | +1.74 |
| Martin ratioReturn relative to average drawdown | 11.87 | 3.76 | +8.11 |
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Drawdowns
VSTBX vs. PBBBX - Drawdown Comparison
The maximum VSTBX drawdown since its inception was -9.34%, smaller than the maximum PBBBX drawdown of -23.00%. Use the drawdown chart below to compare losses from any high point for VSTBX and PBBBX.
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Drawdown Indicators
| VSTBX | PBBBX | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -9.34% | -23.00% | +13.66% |
Max Drawdown (1Y)Largest decline over 1 year | -1.31% | -3.30% | +1.99% |
Max Drawdown (3Y)Largest decline over 3 years | -1.31% | -6.39% | +5.08% |
Max Drawdown (5Y)Largest decline over 5 years | -9.34% | -23.00% | +13.66% |
Max Drawdown (10Y)Largest decline over 10 years | -9.34% | -23.00% | +13.66% |
Current DrawdownCurrent decline from peak | -0.19% | -1.49% | +1.30% |
Average DrawdownAverage peak-to-trough decline | -0.95% | -3.48% | +2.53% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 0.33% | 1.12% | -0.79% |
Volatility
VSTBX vs. PBBBX - Volatility Comparison
The current volatility for Vanguard Short-Term Corporate Bond Index Fund Institutional Shares (VSTBX) is 0.63%, while PIA BBB Bond Fund (PBBBX) has a volatility of 1.12%. This indicates that VSTBX experiences smaller price fluctuations and is considered to be less risky than PBBBX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
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Volatility by Period
| VSTBX | PBBBX | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 0.63% | 1.12% | -0.49% |
Volatility (6M)Calculated over the trailing 6-month period | 1.37% | 3.19% | -1.82% |
Volatility (1Y)Calculated over the trailing 1-year period | 1.78% | 4.09% | -2.31% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 2.72% | 6.67% | -3.95% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 2.38% | 6.02% | -3.64% |
VSTBX vs. PBBBX - Expense Ratio Comparison
VSTBX has a 0.05% expense ratio, which is lower than PBBBX's 0.15% 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
VSTBX vs. PBBBX - Dividend Comparison
VSTBX's dividend yield for the trailing twelve months is around 4.45%, more than PBBBX's 3.80% yield.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
PBBBX PIA BBB Bond Fund | 3.80% | 4.02% | 3.82% | 3.57% | 3.24% | 2.85% | 3.16% | 3.78% | 4.20% | 3.75% | 3.95% | 4.12% |
VSTBX Vanguard Short-Term Corporate Bond Index Fund Institutional Shares | 4.45% | 4.34% | 4.29% | 3.09% | 2.00% | 1.80% | 2.27% | 5.40% | 2.67% | 2.27% | 1.96% | 2.25% |
Frequently Asked Questions
VSTBX and PBBBX have a correlation of 0.78, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.
PBBBX has higher volatility (1.12%) compared to VSTBX (0.63%). In terms of maximum drawdown, VSTBX dropped -9.34% vs PBBBX's -23.00%.
VSTBX currently has the higher Sharpe Ratio (2.24 vs 1.03), 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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