SSMKX vs. FSOPX
SSMKX (State Street Small/Mid Cap Equity Index Fund) and FSOPX (Fidelity Series Small Cap Opportunities Fund) are both mutual funds - SSMKX is a Mid Cap Blend Equities fund managed by State Street, while FSOPX is a Small Cap Blend Equities fund managed by Fidelity. Over the past 10 years, SSMKX returned 12.48%/yr vs 12.77%/yr for FSOPX. With a 0.95 correlation, they move nearly in lockstep. SSMKX charges 0.04%/yr vs 0.00%/yr for FSOPX.
Performance
SSMKX vs. FSOPX - Performance Comparison
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Returns By Period
In the year-to-date period, SSMKX achieves a 14.17% return, which is significantly lower than FSOPX's 16.83% return. Both investments have delivered pretty close results over the past 10 years, with SSMKX having a 12.48% annualized return and FSOPX not far ahead at 12.77%.
SSMKX
- 1D
- 1.00%
- 1M
- 5.71%
- YTD
- 14.17%
- 6M
- 13.00%
- 1Y
- 29.82%
- 3Y*
- 20.36%
- 5Y*
- 7.43%
- 10Y*
- 12.48%
FSOPX
- 1D
- 0.85%
- 1M
- 1.12%
- YTD
- 16.83%
- 6M
- 15.66%
- 1Y
- 40.89%
- 3Y*
- 21.01%
- 5Y*
- 11.01%
- 10Y*
- 12.77%
SSMKX vs. FSOPX - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
SSMKX State Street Small/Mid Cap Equity Index Fund | 14.17% | 12.77% | 17.20% | 25.20% | -25.49% | 12.38% | 32.41% | 27.82% | -9.02% | 18.16% |
FSOPX Fidelity Series Small Cap Opportunities Fund | 16.83% | 15.81% | 15.31% | 20.38% | -17.82% | 23.39% | 17.03% | 29.92% | -8.12% | 11.10% |
Correlation
The correlation between SSMKX and FSOPX is 0.91, 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 | 0.91 |
Correlation (3Y) Calculated over the trailing 3-year period | 0.94 |
Correlation (5Y) Calculated over the trailing 5-year period | 0.95 |
Correlation (10Y) Calculated over the trailing 10-year period | 0.95 |
Correlation (All Time) Calculated using the full available price history since Jan 5, 2016 | 0.95 |
The correlation between SSMKX and FSOPX has been stable across timeframes, ranging from 0.91 to 0.95 - a consistent structural relationship.
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Return for Risk
SSMKX vs. FSOPX — Risk / Return Rank
SSMKX
FSOPX
SSMKX vs. FSOPX - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for State Street Small/Mid Cap Equity Index Fund (SSMKX) and Fidelity Series Small Cap Opportunities Fund (FSOPX). 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.
| SSMKX | FSOPX | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | -0.54 | ||
| Sortino ratioReturn per unit of downside risk | -0.78 | ||
| Omega ratioGain probability vs. loss probability | 1.32 | 1.41 | -0.09 |
| Calmar ratioReturn relative to maximum drawdown | 3.16 | 4.35 | -1.18 |
| Martin ratioReturn relative to average drawdown | 11.48 | 17.03 | -5.55 |
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month. | |||
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Sharpe Ratios by Period
| SSMKX | FSOPX | Difference | |
|---|---|---|---|
Sharpe Ratio (1Y)Calculated over the trailing 1-year period | 1.88 | 2.42 | -0.54 |
Sharpe Ratio (5Y)Calculated over the trailing 5-year period | 0.34 | 0.51 | -0.17 |
Sharpe Ratio (10Y)Calculated over the trailing 10-year period | 0.56 | 0.58 | -0.02 |
Sharpe Ratio (All Time)Calculated using the full available price history | 0.57 | 0.39 | +0.18 |
Drawdowns
SSMKX vs. FSOPX - Drawdown Comparison
The maximum SSMKX drawdown since its inception was -41.65%, smaller than the maximum FSOPX drawdown of -61.75%. Use the drawdown chart below to compare losses from any high point for SSMKX and FSOPX.
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Drawdown Indicators
| SSMKX | FSOPX | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -41.65% | -61.75% | +20.10% |
Max Drawdown (1Y)Largest decline over 1 year | -10.03% | -9.99% | -0.04% |
Max Drawdown (3Y)Largest decline over 3 years | -26.31% | -27.17% | +0.86% |
Max Drawdown (5Y)Largest decline over 5 years | -35.19% | -30.06% | -5.13% |
Max Drawdown (10Y)Largest decline over 10 years | -41.65% | -39.15% | -2.50% |
Current DrawdownCurrent decline from peak | 0.00% | -1.66% | +1.66% |
Average DrawdownAverage peak-to-trough decline | -8.70% | -10.37% | +1.67% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 2.76% | 2.54% | +0.22% |
Volatility
SSMKX vs. FSOPX - Volatility Comparison
The current volatility for State Street Small/Mid Cap Equity Index Fund (SSMKX) is 4.70%, while Fidelity Series Small Cap Opportunities Fund (FSOPX) has a volatility of 5.26%. This indicates that SSMKX experiences smaller price fluctuations and is considered to be less risky than FSOPX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
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Volatility by Period
| SSMKX | FSOPX | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 4.70% | 5.26% | -0.56% |
Volatility (6M)Calculated over the trailing 6-month period | 12.35% | 13.46% | -1.11% |
Volatility (1Y)Calculated over the trailing 1-year period | 16.90% | 17.92% | -1.02% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 22.25% | 21.70% | +0.55% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 22.26% | 21.99% | +0.27% |
SSMKX vs. FSOPX - Expense Ratio Comparison
SSMKX has a 0.05% expense ratio, which is higher than FSOPX's 0.00% 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
SSMKX vs. FSOPX - Dividend Comparison
SSMKX's dividend yield for the trailing twelve months is around 4.47%, more than FSOPX's 3.78% yield.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
FSOPX Fidelity Series Small Cap Opportunities Fund | 3.78% | 4.41% | 9.41% | 0.98% | 5.16% | 30.85% | 2.01% | 6.67% | 13.99% | 10.31% | 0.69% | 5.93% |
SSMKX State Street Small/Mid Cap Equity Index Fund | 4.47% | 5.10% | 2.12% | 2.56% | 17.09% | 9.69% | 1.47% | 5.75% | 3.68% | 5.52% | 1.30% | 0.00% |
Frequently Asked Questions
With a correlation of 0.91, SSMKX and FSOPX 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.
FSOPX has higher volatility (5.26%) compared to SSMKX (4.70%). In terms of maximum drawdown, SSMKX dropped -41.65% vs FSOPX's -61.75%.
FSOPX currently has the higher Sharpe Ratio (2.42 vs 1.88), 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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