UNG vs. IWM
UNG (United States Natural Gas Fund LP) and IWM (iShares Russell 2000 ETF) are both exchange-traded funds - UNG is a Oil & Gas fund tracking the Front Month Natural Gas, while IWM is a Small Cap Blend Equities fund tracking the Russell 2000 Index. Both are passively managed. Over the past 10 years, UNG returned -21.38%/yr vs 11.27%/yr for IWM. At a 0.04 correlation, their price movements are largely independent. UNG charges 1.28%/yr vs 0.19%/yr for IWM.
Performance
UNG vs. IWM - Performance Comparison
Loading charts...
Returns By Period
In the year-to-date period, UNG achieves a -7.42% return, which is significantly lower than IWM's 19.22% return. Over the past 10 years, UNG has underperformed IWM with an annualized return of -21.38%, while IWM has yielded a comparatively higher 11.27% annualized return.
UNG
- 1D
- 1.70%
- 1M
- 3.37%
- YTD
- -7.42%
- 6M
- -10.84%
- 1Y
- -29.37%
- 3Y*
- -23.83%
- 5Y*
- -24.47%
- 10Y*
- -21.38%
IWM
- 1D
- 0.87%
- 1M
- 3.64%
- YTD
- 19.22%
- 6M
- 16.00%
- 1Y
- 39.16%
- 3Y*
- 17.23%
- 5Y*
- 6.07%
- 10Y*
- 11.27%
UNG vs. IWM - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
UNG United States Natural Gas Fund LP | -7.42% | -27.07% | -17.11% | -64.04% | 12.89% | 35.76% | -45.43% | -31.77% | 5.96% | -37.58% |
IWM iShares Russell 2000 ETF | 19.22% | 12.66% | 11.38% | 16.83% | -20.48% | 14.54% | 20.03% | 25.39% | -11.12% | 14.58% |
Correlation
The correlation between UNG and IWM is -0.27, meaning they tend to move in opposite directions. This is especially valuable for risk management - when one declines, the other has historically tended to hold steady or rise.
| Correlation | |
|---|---|
Correlation (1Y) Calculated over the trailing 1-year period | -0.27 |
Correlation (3Y) Calculated over the trailing 3-year period | -0.07 |
Correlation (5Y) Calculated over the trailing 5-year period | 0.03 |
Correlation (10Y) Calculated over the trailing 10-year period | 0.04 |
Correlation (All Time) Calculated using the full available price history since Apr 18, 2007 | 0.04 |
The correlation between UNG and IWM shifts across timeframes, from -0.27 (1 year) to 0.04 (all time), reflecting how their relationship changes across market environments.
Compare stocks, funds, or ETFs
Search for stocks, ETFs, and funds for a quick comparison or use the comparison tool for more options.
Return for Risk
UNG vs. IWM — Risk / Return Rank
UNG
IWM
UNG vs. IWM - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for United States Natural Gas Fund LP (UNG) 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.
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.
| UNG | IWM | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | -2.48 | ||
| Sortino ratioReturn per unit of downside risk | -3.11 | ||
| Omega ratioGain probability vs. loss probability | 0.95 | 1.33 | -0.37 |
| Calmar ratioReturn relative to maximum drawdown | -0.67 | 3.57 | -4.24 |
| Martin ratioReturn relative to average drawdown | -0.97 | 12.63 | -13.60 |
Loading charts...
Drawdowns
UNG vs. IWM - Drawdown Comparison
The maximum UNG drawdown since its inception was -99.88%, which is greater than IWM's maximum drawdown of -59.05%. Use the drawdown chart below to compare losses from any high point for UNG and IWM.
Loading charts...
Drawdown Indicators
| UNG | IWM | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -99.88% | -59.05% | -40.83% |
Max Drawdown (1Y)Largest decline over 1 year | -43.86% | -11.03% | -32.83% |
Max Drawdown (3Y)Largest decline over 3 years | -68.16% | -27.50% | -40.66% |
Max Drawdown (5Y)Largest decline over 5 years | -92.49% | -31.91% | -60.58% |
Max Drawdown (10Y)Largest decline over 10 years | -93.55% | -41.13% | -52.42% |
Current DrawdownCurrent decline from peak | -99.86% | 0.00% | -99.86% |
Average DrawdownAverage peak-to-trough decline | -89.96% | -10.76% | -79.20% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 30.28% | 3.12% | +27.16% |
Volatility
UNG vs. IWM - Volatility Comparison
United States Natural Gas Fund LP (UNG) has a higher volatility of 12.64% compared to iShares Russell 2000 ETF (IWM) at 7.16%. This indicates that UNG's price experiences larger fluctuations and is considered to be riskier than IWM based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
Loading charts...
Volatility by Period
| UNG | IWM | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 12.64% | 7.16% | +5.48% |
Volatility (6M)Calculated over the trailing 6-month period | 52.01% | 14.29% | +37.72% |
Volatility (1Y)Calculated over the trailing 1-year period | 60.61% | 19.73% | +40.88% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 64.11% | 22.61% | +41.50% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 54.77% | 23.08% | +31.69% |
UNG vs. IWM - Expense Ratio Comparison
UNG has a 1.28% expense ratio, which is higher than IWM's 0.19% expense ratio.
Dividends
UNG vs. IWM - Dividend Comparison
UNG has not paid dividends to shareholders, while IWM's dividend yield for the trailing twelve months is around 0.87%.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
IWM iShares Russell 2000 ETF | 0.87% | 1.04% | 1.15% | 1.35% | 1.48% | 0.94% | 1.04% | 1.26% | 1.40% | 1.26% | 1.38% | 1.54% |
UNG United States Natural Gas Fund LP | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% | 0.00% |
Frequently Asked Questions
UNG and IWM have a correlation of -0.27, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.
UNG has higher volatility (12.64%) compared to IWM (7.16%). In terms of maximum drawdown, UNG dropped -99.88% vs IWM's -59.05%.
On 10-year performance, IWM leads with 11.27% vs -21.38% for UNG. On fees, IWM is cheaper at 0.19% per year. On volatility, IWM has been the lower-risk option at 7.16%. The better choice depends on whether you care most about return, fees, risk, or income.
Over the 10-year period, IWM has performed better with a 11.27% return vs -21.38%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.
IWM is cheaper with a 0.19% expense ratio, compared with 1.28% for UNG.
IWM has the higher dividend yield at 0.87%, compared with 0.00% for UNG.
UNG is categorized as Oil & Gas, while IWM is Small Cap Blend Equities. UNG tracks Front Month Natural Gas, while IWM tracks Russell 2000 Index. They also come from different issuers: Concierge Technologies and iShares. Their fees differ too: 1.28% for UNG and 0.19% for IWM.
IWM currently has the higher Sharpe Ratio (1.99 vs -0.49), 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.
Find the right allocation for UNG and IWM
Add both to a portfolio and optimize allocations for your target — whether that's maximizing returns, minimizing drawdowns, or balancing risk across holdings.
Open Portfolio Optimizer