VSIGX vs. VAIPX

Last updated Jun 4, 2026

VSIGX (Vanguard Intermediate-Term Treasury Index Fund Admiral Shares) and VAIPX (Vanguard Inflation-Protected Securities Fund Admiral Shares) are both mutual funds - VSIGX is a Government Bonds fund managed by Vanguard, while VAIPX is a Inflation-Protected Bonds fund managed by Vanguard. Over the past 10 years, VSIGX returned 1.25%/yr vs 2.64%/yr for VAIPX. A 0.80 correlation means they provide meaningful diversification when combined. VSIGX charges 0.07%/yr vs 0.10%/yr for VAIPX.

Performance

VSIGX vs. VAIPX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard Intermediate-Term Treasury Index Fund Admiral Shares (VSIGX) and Vanguard Inflation-Protected Securities Fund Admiral Shares (VAIPX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, VSIGX achieves a -0.33% return, which is significantly lower than VAIPX's 1.65% return. Over the past 10 years, VSIGX has underperformed VAIPX with an annualized return of 1.25%, while VAIPX has yielded a comparatively higher 2.64% annualized return.

VSIGX

• 1D: 0.00%
• 1M: 0.02%
• YTD: -0.33%
• 6M: -0.45%
• 1Y: 3.69%
• 3Y*: 3.55%
• 5Y*: 0.18%
• 10Y*: 1.25%

VAIPX

• 1D: 0.00%
• 1M: 0.13%
• YTD: 1.65%
• 6M: 1.27%
• 1Y: 5.31%
• 3Y*: 4.04%
• 5Y*: 1.17%
• 10Y*: 2.64%

*Multi-year figures are annualized to reflect compound growth (CAGR)

VSIGX vs. VAIPX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
VSIGX Vanguard Intermediate-Term Treasury Index Fund Admiral Shares	-0.33%	7.36%	1.65%	4.39%	-10.69%	-2.60%	7.65%	6.26%	1.35%	1.58%
VAIPX Vanguard Inflation-Protected Securities Fund Admiral Shares	1.65%	6.87%	1.85%	3.83%	-11.92%	5.69%	10.96%	8.16%	-1.39%	2.91%

Correlation

The correlation between VSIGX and VAIPX is 0.85, 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	0.85
Correlation (3Y) Calculated over the trailing 3-year period	0.89
Correlation (5Y) Calculated over the trailing 5-year period	0.81
Correlation (10Y) Calculated over the trailing 10-year period	0.79
Correlation (All Time) Calculated using the full available price history since Nov 24, 2009	0.80

The correlation between VSIGX and VAIPX has been stable across timeframes, ranging from 0.79 to 0.89 - a consistent structural relationship.

Return for Risk

VSIGX vs. VAIPX — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.

VSIGX

VSIGX Risk / Return Rank: 14
VSIGX Sharpe Ratio Rank: 15
VSIGX Sortino Ratio Rank: 15
VSIGX Omega Ratio Rank: 14
VSIGX Calmar Ratio Rank: 14
VSIGX Martin Ratio Rank: 13

VAIPX

VAIPX Risk / Return Rank: 34
VAIPX Sharpe Ratio Rank: 30
VAIPX Sortino Ratio Rank: 32
VAIPX Omega Ratio Rank: 28
VAIPX Calmar Ratio Rank: 44
VAIPX Martin Ratio Rank: 36

The rank (0–100) shows how this investment's returns compare to the risk taken. Higher = better. Based on the past 12 months of data, combining Sharpe, Sortino, and other metrics used by quantitative funds and institutional investors.

VSIGX vs. VAIPX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard Intermediate-Term Treasury Index Fund Admiral Shares (VSIGX) and Vanguard Inflation-Protected Securities Fund Admiral Shares (VAIPX). 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.

	VSIGX	VAIPX	Difference
Sharpe ratio Return per unit of total volatility	1.09	1.54	-0.46
Sortino ratio Return per unit of downside risk	1.64	2.35	-0.71
Omega ratio Gain probability vs. loss probability	1.19	1.28	-0.09
Calmar ratio Return relative to maximum drawdown	1.28	2.53	-1.25
Martin ratio Return relative to average drawdown	3.88	8.02	-4.14
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VSIGX vs. VAIPX - Sharpe Ratio Comparison

The current VSIGX Sharpe Ratio is 1.09, which is comparable to the VAIPX Sharpe Ratio of 1.54. The chart below compares the historical Sharpe Ratios of VSIGX and VAIPX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Sharpe Ratios by Period

	VSIGX	VAIPX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.09	1.54	-0.46
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.03	0.20	-0.16
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.28	0.50	-0.22
Sharpe Ratio (All Time) Calculated using the full available price history	0.51	0.52	-0.01

Drawdowns

VSIGX vs. VAIPX - Drawdown Comparison

The maximum VSIGX drawdown since its inception was -16.15%, which is greater than VAIPX's maximum drawdown of -15.04%. Use the drawdown chart below to compare losses from any high point for VSIGX and VAIPX.

Drawdown Indicators

	VSIGX	VAIPX	Difference
Max Drawdown Largest peak-to-trough decline	-16.15%	-15.04%	-1.11%
Max Drawdown (1Y) Largest decline over 1 year	-2.86%	-2.05%	-0.81%
Max Drawdown (3Y) Largest decline over 3 years	-4.24%	-4.52%	+0.28%
Max Drawdown (5Y) Largest decline over 5 years	-15.07%	-14.40%	-0.67%
Max Drawdown (10Y) Largest decline over 10 years	-16.15%	-14.40%	-1.75%
Current Drawdown Current decline from peak	-2.06%	-0.09%	-1.97%
Average Drawdown Average peak-to-trough decline	-3.51%	-3.81%	+0.30%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.94%	0.65%	+0.29%

Volatility

VSIGX vs. VAIPX - Volatility Comparison

Vanguard Intermediate-Term Treasury Index Fund Admiral Shares (VSIGX) has a higher volatility of 1.10% compared to Vanguard Inflation-Protected Securities Fund Admiral Shares (VAIPX) at 0.97%. This indicates that VSIGX's price experiences larger fluctuations and is considered to be riskier than VAIPX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VSIGX	VAIPX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.10%	0.97%	+0.13%
Volatility (6M) Calculated over the trailing 6-month period	2.37%	2.32%	+0.05%
Volatility (1Y) Calculated over the trailing 1-year period	3.37%	3.38%	-0.01%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	5.33%	5.99%	-0.66%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	4.45%	5.32%	-0.87%

VSIGX vs. VAIPX - Expense Ratio Comparison

VSIGX has a 0.07% expense ratio, which is lower than VAIPX's 0.10% 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

VSIGX vs. VAIPX - Dividend Comparison

VSIGX's dividend yield for the trailing twelve months is around 3.83%, less than VAIPX's 4.49% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
VAIPX Vanguard Inflation-Protected Securities Fund Admiral Shares	4.49%	4.74%	4.17%	4.31%	8.45%	5.13%	1.38%	2.29%	3.12%	2.41%	3.49%	0.88%
VSIGX Vanguard Intermediate-Term Treasury Index Fund Admiral Shares	3.83%	3.76%	3.95%	2.70%	1.71%	1.66%	2.21%	2.21%	2.05%	1.67%	1.56%	1.70%

Frequently Asked Questions

Can I hold both VSIGX and VAIPX in my portfolio?

VSIGX and VAIPX have a correlation of 0.85, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, VSIGX or VAIPX?

VSIGX has higher volatility (1.10%) compared to VAIPX (0.97%). In terms of maximum drawdown, VSIGX dropped -16.15% vs VAIPX's -15.04%.

Which has better risk-adjusted returns?

VAIPX currently has the higher Sharpe Ratio (1.54 vs 1.09), 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.