VAIPX vs. FSPWX

Last updated Jul 14, 2026

VAIPX (Vanguard Inflation-Protected Securities Fund Admiral Shares) and FSPWX (Fidelity SAI Inflation-Protected Bond Index Fund) are both Inflation-Protected Bonds funds tracking the Bloomberg U.S. Treasury Inflation Protected Securities Index, from Vanguard and Fidelity respectively. Both are passively managed. Over the past year, VAIPX returned 3.36% vs 2.01% for FSPWX. Their correlation of 0.93 suggests significant overlap in exposure. VAIPX charges 0.10%/yr vs 0.05%/yr for FSPWX.

Performance

VAIPX vs. FSPWX - Performance Comparison

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

Returns By Period

In the year-to-date period, VAIPX achieves a 0.85% return, which is significantly higher than FSPWX's -0.36% return.

VAIPX

• 1D: 0.00%
• 1M: -0.32%
• 6M: 0.68%
• YTD: 0.85%
• 1Y: 3.36%
• 3Y*: 4.14%
• 5Y*: 0.76%
• 10Y*: 2.38%

FSPWX

• 1D: -1.38%
• 1M: -1.67%
• 6M: -0.65%
• YTD: -0.36%
• 1Y: 2.01%
• 3Y*: —
• 5Y*: —
• 10Y*: —

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

VAIPX vs. FSPWX - Yearly Performance Comparison

	2026 (YTD)	2025	2024
VAIPX Vanguard Inflation-Protected Securities Fund Admiral Shares	0.85%	6.87%	-1.75%
FSPWX Fidelity SAI Inflation-Protected Bond Index Fund	-0.36%	6.76%	-1.32%

Correlation

The correlation between VAIPX and FSPWX is 0.94, 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	0.94
Correlation (All Time) Calculated using the full available price history since Aug 22, 2024	0.93

The correlation between VAIPX and FSPWX has been stable across timeframes, ranging from 0.93 to 0.94 - a consistent structural relationship.

Return for Risk

VAIPX vs. FSPWX — Risk / Return Rank

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

VAIPX

VAIPX Risk / Return Rank: 23
VAIPX Sharpe Ratio Rank: 20
VAIPX Sortino Ratio Rank: 20
VAIPX Omega Ratio Rank: 18
VAIPX Calmar Ratio Rank: 29
VAIPX Martin Ratio Rank: 26

FSPWX

FSPWX Risk / Return Rank: 10
FSPWX Sharpe Ratio Rank: 9
FSPWX Sortino Ratio Rank: 8
FSPWX Omega Ratio Rank: 9
FSPWX Calmar Ratio Rank: 13
FSPWX Martin Ratio Rank: 14

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.

VAIPX vs. FSPWX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard Inflation-Protected Securities Fund Admiral Shares (VAIPX) and Fidelity SAI Inflation-Protected Bond Index Fund (FSPWX). 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.

	VAIPX	FSPWX	Difference
Sharpe ratio: Return per unit of total volatility	0.94	0.50	+0.44
Sortino ratio: Return per unit of downside risk	1.40	0.71	+0.69
Omega ratio: Gain probability vs. loss probability	1.16	1.09	+0.07
Calmar ratio: Return relative to maximum drawdown	1.56	0.85	+0.71
Martin ratio: Return relative to average drawdown	4.74	2.73	+2.01

VAIPX vs. FSPWX - Sharpe Ratio Comparison

The current VAIPX Sharpe Ratio is 0.94, which is higher than the FSPWX Sharpe Ratio of 0.50. The chart below compares the historical Sharpe Ratios of VAIPX and FSPWX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Drawdowns

VAIPX vs. FSPWX - Drawdown Comparison

The maximum VAIPX drawdown since its inception was -15.04%, which is greater than FSPWX's maximum drawdown of -3.84%. Use the drawdown chart below to compare losses from any high point for VAIPX and FSPWX.

Drawdown Indicators

	VAIPX	FSPWX	Difference
Max Drawdown Largest peak-to-trough decline	-15.04%	-3.84%	-11.20%
Max Drawdown (1Y) Largest decline over 1 year	-2.05%	-2.15%	+0.10%
Max Drawdown (3Y) Largest decline over 3 years	-4.48%	—	—
Max Drawdown (5Y) Largest decline over 5 years	-14.40%	—	—
Max Drawdown (10Y) Largest decline over 10 years	-14.40%	—	—
Current Drawdown Current decline from peak	-0.87%	-2.15%	+1.28%
Average Drawdown Average peak-to-trough decline	-3.79%	-0.96%	-2.83%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.67%	0.67%	0.00%

Volatility

VAIPX vs. FSPWX - Volatility Comparison

The current volatility for Vanguard Inflation-Protected Securities Fund Admiral Shares (VAIPX) is 1.16%, while Fidelity SAI Inflation-Protected Bond Index Fund (FSPWX) has a volatility of 1.80%. This indicates that VAIPX experiences smaller price fluctuations and is considered to be less risky than FSPWX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VAIPX	FSPWX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.16%	1.80%	-0.64%
Volatility (6M) Calculated over the trailing 6-month period	2.53%	2.85%	-0.32%
Volatility (1Y) Calculated over the trailing 1-year period	3.39%	3.64%	-0.25%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	5.98%	4.18%	+1.80%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	5.32%	4.18%	+1.14%

VAIPX vs. FSPWX - Expense Ratio Comparison

VAIPX has a 0.10% expense ratio, which is higher than FSPWX's 0.05% expense ratio. However, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

VAIPX vs. FSPWX - Dividend Comparison

VAIPX's dividend yield for the trailing twelve months is around 5.06%, more than FSPWX's 3.04% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FSPWX Fidelity SAI Inflation-Protected Bond Index Fund	3.04%	4.19%	0.69%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
VAIPX Vanguard Inflation-Protected Securities Fund Admiral Shares	5.06%	4.74%	4.17%	4.31%	8.45%	5.13%	1.38%	2.29%	3.12%	2.41%	3.49%	0.88%

Frequently Asked Questions

Can I hold both VAIPX and FSPWX in my portfolio?

With a correlation of 0.94, VAIPX and FSPWX 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.

Which is riskier, VAIPX or FSPWX?

FSPWX has higher volatility (1.80%) compared to VAIPX (1.16%). In terms of maximum drawdown, VAIPX dropped -15.04% vs FSPWX's -3.84%.

Which has better risk-adjusted returns?

VAIPX currently has the higher Sharpe Ratio (0.94 vs 0.50), 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.