REK vs. SSO

Last updated Jun 4, 2026

REK (ProShares Short Real Estate) and SSO (ProShares Ultra S&P500) are both exchange-traded funds - REK is a REIT fund tracking the DJ Global United States (All) / Real Estate -SS (-100%), while SSO is a Leveraged Equities fund tracking the S&P 500. Both are passively managed. Over the past 10 years, REK returned -6.20%/yr vs 24.21%/yr for SSO. At a correlation of -0.61, they often move in opposite directions. REK charges 0.95%/yr vs 0.87%/yr for SSO.

Performance

REK vs. SSO - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in ProShares Short Real Estate (REK) and ProShares Ultra S&P500 (SSO). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, REK achieves a -6.58% return, which is significantly lower than SSO's 19.37% return. Over the past 10 years, REK has underperformed SSO with an annualized return of -6.20%, while SSO has yielded a comparatively higher 24.21% annualized return.

REK

• 1D: -0.49%
• 1M: 1.33%
• YTD: -6.58%
• 6M: -5.51%
• 1Y: -2.96%
• 3Y*: -3.69%
• 5Y*: -0.14%
• 10Y*: -6.20%

SSO

• 1D: -1.40%
• 1M: 9.75%
• YTD: 19.37%
• 6M: 18.81%
• 1Y: 52.69%
• 3Y*: 37.56%
• 5Y*: 19.62%
• 10Y*: 24.21%

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

REK vs. SSO - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
REK ProShares Short Real Estate	-6.58%	2.35%	1.42%	-6.61%	29.17%	-30.58%	-11.33%	-20.96%	4.61%	-9.34%
SSO ProShares Ultra S&P500	19.37%	26.19%	43.48%	46.65%	-38.98%	60.57%	21.54%	63.45%	-14.60%	44.35%

Correlation

The correlation between REK and SSO is -0.29, 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	-0.29
Correlation (3Y) Calculated over the trailing 3-year period	-0.44
Correlation (5Y) Calculated over the trailing 5-year period	-0.58
Correlation (10Y) Calculated over the trailing 10-year period	-0.56
Correlation (All Time) Calculated using the full available price history since Mar 19, 2010	-0.61

Over the past year, the inverse relationship between REK and SSO has weakened: their correlation has moved from -0.61 to -0.29, meaning they move in opposite directions less often than they have historically.

REK vs. SSO - Sectors Allocation Comparison

Sectors	REK	SSO
Financial Services	46.7%	11.8%
Basic Materials	-	1.8%
Communication Services	-	11.2%
Consumer Cyclical	-	10.1%
Consumer Defensive	-	4.9%
Energy	-	3.5%
Healthcare	-	8.5%
Industrials	-	8.3%
Real Estate	-	1.9%
Technology	-	35.6%
Utilities	-	2.4%

Return for Risk

REK vs. SSO — Risk / Return Rank

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

REK

REK Risk / Return Rank: 6
REK Sharpe Ratio Rank: 7
REK Sortino Ratio Rank: 6
REK Omega Ratio Rank: 6
REK Calmar Ratio Rank: 6
REK Martin Ratio Rank: 6

SSO

SSO Risk / Return Rank: 62
SSO Sharpe Ratio Rank: 66
SSO Sortino Ratio Rank: 59
SSO Omega Ratio Rank: 60
SSO Calmar Ratio Rank: 58
SSO Martin Ratio Rank: 68

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.

REK vs. SSO - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for ProShares Short Real Estate (REK) and ProShares Ultra S&P500 (SSO). 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.

	REK	SSO	Difference
Sharpe ratio: Return per unit of total volatility	-0.22	2.25	-2.47
Sortino ratio: Return per unit of downside risk	-0.23	2.86	-3.09
Omega ratio: Gain probability vs. loss probability	0.97	1.38	-0.40
Calmar ratio: Return relative to maximum drawdown	-0.29	2.91	-3.21
Martin ratio: Return relative to average drawdown	-0.67	12.80	-13.47
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

REK vs. SSO - Sharpe Ratio Comparison

The current REK Sharpe Ratio is -0.22, which is lower than the SSO Sharpe Ratio of 2.25. The chart below compares the historical Sharpe Ratios of REK and SSO, 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

	REK	SSO	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	-0.22	2.25	-2.47
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.01	0.59	-0.59
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	-0.31	0.68	-0.98
Sharpe Ratio (All Time) Calculated using the full available price history	-0.49	0.42	-0.90

Drawdowns

REK vs. SSO - Drawdown Comparison

The maximum REK drawdown since its inception was -84.57%, roughly equal to the maximum SSO drawdown of -84.67%. Use the drawdown chart below to compare losses from any high point for REK and SSO.

Drawdown Indicators

	REK	SSO	Difference
Max Drawdown Largest peak-to-trough decline	-84.57%	-84.67%	+0.10%
Max Drawdown (1Y) Largest decline over 1 year	-10.23%	-18.17%	+7.94%
Max Drawdown (3Y) Largest decline over 3 years	-26.93%	-35.21%	+8.28%
Max Drawdown (5Y) Largest decline over 5 years	-26.93%	-46.73%	+19.80%
Max Drawdown (10Y) Largest decline over 10 years	-58.67%	-59.34%	+0.67%
Current Drawdown Current decline from peak	-81.95%	-1.40%	-80.55%
Average Drawdown Average peak-to-trough decline	-64.08%	-19.57%	-44.51%
Ulcer Index Depth and duration of drawdowns from previous peaks	4.42%	4.13%	+0.29%

Volatility

REK vs. SSO - Volatility Comparison

The current volatility for ProShares Short Real Estate (REK) is 3.91%, while ProShares Ultra S&P500 (SSO) has a volatility of 5.66%. This indicates that REK experiences smaller price fluctuations and is considered to be less risky than SSO based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	REK	SSO	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.91%	5.66%	-1.75%
Volatility (6M) Calculated over the trailing 6-month period	9.67%	17.78%	-8.11%
Volatility (1Y) Calculated over the trailing 1-year period	13.42%	23.60%	-10.18%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	18.86%	33.65%	-14.79%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	20.30%	35.89%	-15.59%

REK vs. SSO - Expense Ratio Comparison

REK has a 0.95% expense ratio, which is higher than SSO's 0.87% expense ratio.

Dividends

REK vs. SSO - Dividend Comparison

REK's dividend yield for the trailing twelve months is around 3.27%, more than SSO's 0.62% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
REK ProShares Short Real Estate	3.27%	3.43%	6.22%	4.50%	0.48%	0.00%	0.07%	1.28%	0.43%	0.00%	0.00%	0.00%
SSO ProShares Ultra S&P500	0.62%	0.68%	0.85%	0.18%	0.50%	0.18%	0.20%	0.50%	0.75%	0.39%	0.51%	0.63%

Frequently Asked Questions

Can I hold both REK and SSO in my portfolio?

REK and SSO have a correlation of -0.29, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, REK or SSO?

SSO has higher volatility (5.66%) compared to REK (3.91%). In terms of maximum drawdown, REK dropped -84.57% vs SSO's -84.67%.

Which ETF is better, REK or SSO?

On 10-year performance, SSO leads with 24.21% vs -6.20% for REK. On fees, SSO is cheaper at 0.87% per year. On volatility, REK has been the lower-risk option at 3.91%. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF has performed better, REK or SSO?

Over the 10-year period, SSO has performed better with a 24.21% return vs -6.20%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

Which ETF is cheaper, REK or SSO?

SSO is cheaper with a 0.87% expense ratio, compared with 0.95% for REK.

Which ETF pays a higher dividend yield, REK or SSO?

REK has the higher dividend yield at 3.27%, compared with 0.62% for SSO.

What is the main difference between REK and SSO?

REK is categorized as REIT, while SSO is Leveraged Equities. REK tracks DJ Global United States (All) / Real Estate -SS (-100%), while SSO tracks S&P 500. Their fees differ too: 0.95% for REK and 0.87% for SSO.

Which has better risk-adjusted returns?

SSO currently has the higher Sharpe Ratio (2.25 vs -0.22), 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.