BSIIX vs. WFSPX
BSIIX (BlackRock Strategic Income Opportunities Fund Class I) and WFSPX (iShares S&P 500 Index Fund Class K) are both mutual funds - BSIIX is a Total Bond Market fund managed by BlackRock, while WFSPX is a S&P 500 fund tracking the S&P 500 Index. Over the past 10 years, BSIIX returned 3.84%/yr vs 15.68%/yr for WFSPX. At a 0.23 correlation, their price movements are largely independent. BSIIX charges 0.69%/yr vs 0.03%/yr for WFSPX.
Performance
BSIIX vs. WFSPX - Performance Comparison
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Returns By Period
In the year-to-date period, BSIIX achieves a 1.79% return, which is significantly lower than WFSPX's 9.77% return. Over the past 10 years, BSIIX has underperformed WFSPX with an annualized return of 3.84%, while WFSPX has yielded a comparatively higher 15.68% annualized return.
BSIIX
- 1D
- -0.20%
- 1M
- 0.82%
- YTD
- 1.79%
- 6M
- 2.32%
- 1Y
- 6.62%
- 3Y*
- 6.76%
- 5Y*
- 2.95%
- 10Y*
- 3.84%
WFSPX
- 1D
- -0.36%
- 1M
- 0.10%
- YTD
- 9.77%
- 6M
- 8.77%
- 1Y
- 25.45%
- 3Y*
- 21.35%
- 5Y*
- 13.57%
- 10Y*
- 15.68%
BSIIX vs. WFSPX - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
BSIIX BlackRock Strategic Income Opportunities Fund Class I | 1.79% | 8.59% | 5.22% | 6.18% | -6.14% | 0.80% | 7.22% | 7.65% | -0.42% | 4.89% |
WFSPX iShares S&P 500 Index Fund Class K | 9.77% | 17.83% | 24.94% | 26.25% | -18.14% | 28.63% | 18.43% | 31.45% | -4.83% | 21.27% |
Correlation
The correlation between BSIIX and WFSPX is 0.48, which is low. Their price movements are largely independent, making them effective diversification partners.
| Correlation | |
|---|---|
Correlation (1Y) Calculated over the trailing 1-year period | 0.48 |
Correlation (3Y) Calculated over the trailing 3-year period | 0.32 |
Correlation (5Y) Calculated over the trailing 5-year period | 0.32 |
Correlation (10Y) Calculated over the trailing 10-year period | 0.32 |
Correlation (All Time) Calculated using the full available price history since Feb 7, 2008 | 0.23 |
Over the past year, BSIIX and WFSPX have become more correlated (0.48) than their long-term average of 0.23, meaning their price movements have been converging.
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Return for Risk
BSIIX vs. WFSPX — Risk / Return Rank
BSIIX
WFSPX
BSIIX vs. WFSPX - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for BlackRock Strategic Income Opportunities Fund Class I (BSIIX) and iShares S&P 500 Index Fund Class K (WFSPX). 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.
| BSIIX | WFSPX | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | +0.13 | ||
| Sortino ratioReturn per unit of downside risk | +0.69 | ||
| Omega ratioGain probability vs. loss probability | 1.47 | 1.39 | +0.08 |
| Calmar ratioReturn relative to maximum drawdown | 2.38 | 3.01 | -0.63 |
| Martin ratioReturn relative to average drawdown | 9.19 | 13.58 | -4.40 |
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Drawdowns
BSIIX vs. WFSPX - Drawdown Comparison
The maximum BSIIX drawdown since its inception was -18.76%, smaller than the maximum WFSPX drawdown of -58.21%. Use the drawdown chart below to compare losses from any high point for BSIIX and WFSPX.
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Drawdown Indicators
| BSIIX | WFSPX | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -18.76% | -58.21% | +39.45% |
Max Drawdown (1Y)Largest decline over 1 year | -2.84% | -8.90% | +6.06% |
Max Drawdown (3Y)Largest decline over 3 years | -2.84% | -18.74% | +15.90% |
Max Drawdown (5Y)Largest decline over 5 years | -9.13% | -24.51% | +15.38% |
Max Drawdown (10Y)Largest decline over 10 years | -9.91% | -33.74% | +23.83% |
Current DrawdownCurrent decline from peak | -0.51% | -1.72% | +1.21% |
Average DrawdownAverage peak-to-trough decline | -1.80% | -12.76% | +10.96% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 0.73% | 1.97% | -1.24% |
Volatility
BSIIX vs. WFSPX - Volatility Comparison
The current volatility for BlackRock Strategic Income Opportunities Fund Class I (BSIIX) is 0.92%, while iShares S&P 500 Index Fund Class K (WFSPX) has a volatility of 4.67%. This indicates that BSIIX experiences smaller price fluctuations and is considered to be less risky than WFSPX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
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Volatility by Period
| BSIIX | WFSPX | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 0.92% | 4.67% | -3.75% |
Volatility (6M)Calculated over the trailing 6-month period | 2.37% | 9.83% | -7.46% |
Volatility (1Y)Calculated over the trailing 1-year period | 2.97% | 12.49% | -9.52% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 3.65% | 16.97% | -13.32% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 3.15% | 18.07% | -14.92% |
BSIIX vs. WFSPX - Expense Ratio Comparison
BSIIX has a 0.69% expense ratio, which is higher than WFSPX's 0.03% expense ratio.
Dividends
BSIIX vs. WFSPX - Dividend Comparison
BSIIX's dividend yield for the trailing twelve months is around 5.16%, more than WFSPX's 1.59% yield.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
BSIIX BlackRock Strategic Income Opportunities Fund Class I | 5.16% | 5.07% | 4.75% | 3.33% | 3.58% | 2.98% | 2.92% | 3.54% | 3.32% | 3.45% | 2.91% | 3.19% |
WFSPX iShares S&P 500 Index Fund Class K | 1.59% | 1.72% | 1.41% | 1.50% | 2.02% | 1.82% | 1.66% | 1.99% | 2.00% | 1.62% | 2.37% | 2.49% |
Frequently Asked Questions
BSIIX and WFSPX have a correlation of 0.48, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.
WFSPX has higher volatility (4.67%) compared to BSIIX (0.92%). In terms of maximum drawdown, BSIIX dropped -18.76% vs WFSPX's -58.21%.
BSIIX currently has the higher Sharpe Ratio (2.28 vs 2.15), 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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