BIIPX vs. FSPWX

Last updated Jun 4, 2026

BIIPX (iShares Short-Term TIPS Bond Index Fund) and FSPWX (Fidelity SAI Inflation-Protected Bond Index Fund) are both Inflation-Protected Bonds funds. Over the past year, BIIPX returned 4.68% vs 5.38% for FSPWX. A 0.70 correlation means they provide meaningful diversification when combined. BIIPX charges 0.08%/yr vs 0.05%/yr for FSPWX.

Performance

BIIPX vs. FSPWX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares Short-Term TIPS Bond Index Fund (BIIPX) 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, BIIPX achieves a 1.98% return, which is significantly higher than FSPWX's 1.83% return.

BIIPX

• 1D: 0.00%
• 1M: 0.12%
• YTD: 1.98%
• 6M: 2.04%
• 1Y: 4.68%
• 3Y*: 5.00%
• 5Y*: 2.84%
• 10Y*: —

FSPWX

• 1D: 0.00%
• 1M: 0.20%
• YTD: 1.83%
• 6M: 1.35%
• 1Y: 5.38%
• 3Y*: —
• 5Y*: —
• 10Y*: —

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

BIIPX vs. FSPWX - Yearly Performance Comparison

	2026 (YTD)	2025	2024
BIIPX iShares Short-Term TIPS Bond Index Fund	1.98%	6.05%	1.26%
FSPWX Fidelity SAI Inflation-Protected Bond Index Fund	1.83%	6.76%	-1.32%

Correlation

The correlation between BIIPX and FSPWX is 0.64, 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	0.64
Correlation (All Time) Calculated using the full available price history since Aug 23, 2024	0.70

The correlation between BIIPX and FSPWX has been stable across timeframes, ranging from 0.64 to 0.70 - a consistent structural relationship.

Return for Risk

BIIPX vs. FSPWX — Risk / Return Rank

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

BIIPX

BIIPX Risk / Return Rank: 75
BIIPX Sharpe Ratio Rank: 47
BIIPX Sortino Ratio Rank: 83
BIIPX Omega Ratio Rank: 76
BIIPX Calmar Ratio Rank: 82
BIIPX Martin Ratio Rank: 85

FSPWX

FSPWX Risk / Return Rank: 36
FSPWX Sharpe Ratio Rank: 30
FSPWX Sortino Ratio Rank: 33
FSPWX Omega Ratio Rank: 30
FSPWX Calmar Ratio Rank: 49
FSPWX Martin Ratio Rank: 37

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.

BIIPX vs. FSPWX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares Short-Term TIPS Bond Index Fund (BIIPX) 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.

	BIIPX	FSPWX	Difference
Sharpe ratio: Return per unit of total volatility	2.03	1.56	+0.46
Sortino ratio: Return per unit of downside risk	3.96	2.39	+1.57
Omega ratio: Gain probability vs. loss probability	1.50	1.29	+0.21
Calmar ratio: Return relative to maximum drawdown	3.76	2.67	+1.09
Martin ratio: Return relative to average drawdown	16.24	8.19	+8.05
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

BIIPX vs. FSPWX - Sharpe Ratio Comparison

The current BIIPX Sharpe Ratio is 2.03, which is comparable to the FSPWX Sharpe Ratio of 1.56. The chart below compares the historical Sharpe Ratios of BIIPX 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.

Sharpe Ratios by Period

	BIIPX	FSPWX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.03	1.56	+0.46
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.92	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	1.12	1.00	+0.12

Drawdowns

BIIPX vs. FSPWX - Drawdown Comparison

The maximum BIIPX drawdown since its inception was -6.46%, which is greater than FSPWX's maximum drawdown of -3.84%. Use the drawdown chart below to compare losses from any high point for BIIPX and FSPWX.

Drawdown Indicators

	BIIPX	FSPWX	Difference
Max Drawdown Largest peak-to-trough decline	-6.46%	-3.84%	-2.62%
Max Drawdown (1Y) Largest decline over 1 year	-1.22%	-1.95%	+0.73%
Max Drawdown (3Y) Largest decline over 3 years	-1.22%	—	—
Max Drawdown (5Y) Largest decline over 5 years	-6.46%	—	—
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-1.08%	-0.98%	-0.10%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.28%	0.64%	-0.36%

Volatility

BIIPX vs. FSPWX - Volatility Comparison

iShares Short-Term TIPS Bond Index Fund (BIIPX) has a higher volatility of 1.21% compared to Fidelity SAI Inflation-Protected Bond Index Fund (FSPWX) at 0.92%. This indicates that BIIPX's price experiences larger fluctuations and is considered to be riskier than FSPWX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	BIIPX	FSPWX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.21%	0.92%	+0.29%
Volatility (6M) Calculated over the trailing 6-month period	1.67%	2.28%	-0.61%
Volatility (1Y) Calculated over the trailing 1-year period	2.27%	3.35%	-1.08%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	3.11%	4.06%	-0.95%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	2.64%	4.06%	-1.42%

BIIPX vs. FSPWX - Expense Ratio Comparison

BIIPX has a 0.08% 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

BIIPX vs. FSPWX - Dividend Comparison

BIIPX's dividend yield for the trailing twelve months is around 4.59%, more than FSPWX's 3.76% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017
BIIPX iShares Short-Term TIPS Bond Index Fund	4.59%	4.64%	4.30%	2.65%	4.56%	4.39%	1.58%	2.27%	2.74%	1.89%
FSPWX Fidelity SAI Inflation-Protected Bond Index Fund	3.76%	4.19%	0.69%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both BIIPX and FSPWX in my portfolio?

BIIPX and FSPWX have a correlation of 0.64, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, BIIPX or FSPWX?

BIIPX has higher volatility (1.21%) compared to FSPWX (0.92%). In terms of maximum drawdown, BIIPX dropped -6.46% vs FSPWX's -3.84%.

Which has better risk-adjusted returns?

BIIPX currently has the higher Sharpe Ratio (2.03 vs 1.56), 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.