FLXSX vs. IWM
FLXSX (Fidelity Flex Small Cap Index Fund) and IWM (iShares Russell 2000 ETF) are both Small Cap Blend Equities funds. Over the past 5 years, FLXSX returned 6.27%/yr vs 6.11%/yr for IWM. With a 1.00 correlation, they move nearly in lockstep. FLXSX charges 0.00%/yr vs 0.19%/yr for IWM.
Performance
FLXSX vs. IWM - Performance Comparison
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Returns By Period
The year-to-date returns for both stocks are quite close, with FLXSX having a 17.21% return and IWM slightly lower at 17.07%.
FLXSX
- 1D
- 0.33%
- 1M
- 3.96%
- YTD
- 17.21%
- 6M
- 16.56%
- 1Y
- 38.39%
- 3Y*
- 17.93%
- 5Y*
- 6.27%
- 10Y*
- —
IWM
- 1D
- -1.37%
- 1M
- 3.52%
- YTD
- 17.07%
- 6M
- 15.83%
- 1Y
- 39.10%
- 3Y*
- 17.88%
- 5Y*
- 6.11%
- 10Y*
- 10.93%
FLXSX vs. IWM - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
FLXSX Fidelity Flex Small Cap Index Fund | 17.21% | 12.02% | 11.67% | 17.11% | -20.29% | 14.84% | 20.06% | 25.69% | -11.13% | 14.28% |
IWM iShares Russell 2000 ETF | 17.07% | 12.66% | 11.38% | 16.83% | -20.48% | 14.54% | 20.03% | 25.39% | -11.12% | 14.15% |
Correlation
The correlation between FLXSX and IWM is 0.99 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.
| Correlation | |
|---|---|
Correlation (1Y) Calculated over the trailing 1-year period | 0.99 |
Correlation (3Y) Calculated over the trailing 3-year period | 0.99 |
Correlation (5Y) Calculated over the trailing 5-year period | 1.00 |
Correlation (All Time) Calculated using the full available price history since Mar 10, 2017 | 1.00 |
The correlation between FLXSX and IWM has been stable across timeframes, ranging from 0.99 to 1.00 - a consistent structural relationship.
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Return for Risk
FLXSX vs. IWM — Risk / Return Rank
FLXSX
IWM
FLXSX vs. IWM - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for Fidelity Flex Small Cap Index Fund (FLXSX) and iShares Russell 2000 ETF (IWM). 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.
| FLXSX | IWM | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | +0.03 | ||
| Sortino ratioReturn per unit of downside risk | 0.00 | ||
| Omega ratioGain probability vs. loss probability | 1.34 | 1.34 | 0.00 |
| Calmar ratioReturn relative to maximum drawdown | 3.35 | 3.56 | -0.21 |
| Martin ratioReturn relative to average drawdown | 11.73 | 12.64 | -0.92 |
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
| FLXSX | IWM | Difference | |
|---|---|---|---|
Sharpe Ratio (1Y)Calculated over the trailing 1-year period | 2.08 | 2.05 | +0.03 |
Sharpe Ratio (5Y)Calculated over the trailing 5-year period | 0.28 | 0.27 | +0.01 |
Sharpe Ratio (10Y)Calculated over the trailing 10-year period | — | 0.48 | — |
Sharpe Ratio (All Time)Calculated using the full available price history | 0.42 | 0.37 | +0.05 |
Drawdowns
FLXSX vs. IWM - Drawdown Comparison
The maximum FLXSX drawdown since its inception was -41.72%, smaller than the maximum IWM drawdown of -59.05%. Use the drawdown chart below to compare losses from any high point for FLXSX and IWM.
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Drawdown Indicators
| FLXSX | IWM | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -41.72% | -59.05% | +17.33% |
Max Drawdown (1Y)Largest decline over 1 year | -12.25% | -11.03% | -1.22% |
Max Drawdown (3Y)Largest decline over 3 years | -27.48% | -27.50% | +0.02% |
Max Drawdown (5Y)Largest decline over 5 years | -31.88% | -31.91% | +0.03% |
Max Drawdown (10Y)Largest decline over 10 years | — | -41.13% | — |
Current DrawdownCurrent decline from peak | -0.19% | -1.49% | +1.30% |
Average DrawdownAverage peak-to-trough decline | -10.44% | -10.77% | +0.33% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 3.48% | 3.10% | +0.38% |
Volatility
FLXSX vs. IWM - Volatility Comparison
The current volatility for Fidelity Flex Small Cap Index Fund (FLXSX) is 5.03%, while iShares Russell 2000 ETF (IWM) has a volatility of 5.75%. This indicates that FLXSX experiences smaller price fluctuations and is considered to be less risky than IWM based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
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Volatility by Period
| FLXSX | IWM | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 5.03% | 5.75% | -0.72% |
Volatility (6M)Calculated over the trailing 6-month period | 14.19% | 13.53% | +0.66% |
Volatility (1Y)Calculated over the trailing 1-year period | 19.72% | 19.20% | +0.52% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 22.66% | 22.52% | +0.14% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 24.00% | 23.04% | +0.96% |
FLXSX vs. IWM - Expense Ratio Comparison
FLXSX has a 0.00% expense ratio, which is lower than IWM's 0.19% 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
FLXSX vs. IWM - Dividend Comparison
FLXSX has not paid dividends to shareholders, while IWM's dividend yield for the trailing twelve months is around 0.88%.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
FLXSX Fidelity Flex Small Cap Index Fund | 0.00% | 0.00% | 1.36% | 1.49% | 1.26% | 2.74% | 1.06% | 2.86% | 2.31% | 0.77% | 0.00% | 0.00% |
IWM iShares Russell 2000 ETF | 0.88% | 1.04% | 1.15% | 1.35% | 1.48% | 0.94% | 1.04% | 1.26% | 1.40% | 1.26% | 1.38% | 1.54% |
Frequently Asked Questions
With a correlation of 0.99, FLXSX and IWM 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.
IWM has higher volatility (5.75%) compared to FLXSX (5.03%). In terms of maximum drawdown, FLXSX dropped -41.72% vs IWM's -59.05%.
FLXSX currently has the higher Sharpe Ratio (2.08 vs 2.05), 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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