CBTA vs. WEEK

Last updated Jun 4, 2026

CBTA (Calamos Bitcoin 80 Series Structured Alt Protection ETF - April) and WEEK (Roundhill Weekly T-Bill ETF) are both exchange-traded funds - CBTA is a Defined Outcome fund tracking the CBOE Bitcoin US ETF Index, while WEEK is a Ultrashort Bond fund actively managed by Roundhill. CBTA is passively managed, while WEEK is actively managed. Over the past year, CBTA returned -28.38% vs 3.81% for WEEK. At a correlation of -0.08, they often move in opposite directions. CBTA charges 0.69%/yr vs 0.19%/yr for WEEK.

Performance

CBTA vs. WEEK - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Calamos Bitcoin 80 Series Structured Alt Protection ETF - April (CBTA) and Roundhill Weekly T-Bill ETF (WEEK). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, CBTA achieves a -23.76% return, which is significantly lower than WEEK's 1.44% return.

CBTA

• 1D: -1.31%
• 1M: -9.26%
• YTD: -23.76%
• 6M: -26.89%
• 1Y: -28.38%
• 3Y*: —
• 5Y*: —
• 10Y*: —

WEEK

• 1D: 0.02%
• 1M: 0.28%
• YTD: 1.44%
• 6M: 1.74%
• 1Y: 3.81%
• 3Y*: —
• 5Y*: —
• 10Y*: —

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

CBTA vs. WEEK - Yearly Performance Comparison

	2026 (YTD)	2025
CBTA Calamos Bitcoin 80 Series Structured Alt Protection ETF - April	-23.76%	11.79%
WEEK Roundhill Weekly T-Bill ETF	1.44%	2.99%

Correlation

The correlation between CBTA and WEEK is -0.08, meaning there is essentially no relationship between their price movements. Each responds to its own set of market drivers, making them strong candidates for combining in a diversified portfolio.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	-0.08
Correlation (All Time) Calculated using the full available price history since Apr 8, 2025	-0.08

Return for Risk

CBTA vs. WEEK — Risk / Return Rank

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

CBTA

CBTA Risk / Return Rank: 2
CBTA Sharpe Ratio Rank: 2
CBTA Sortino Ratio Rank: 2
CBTA Omega Ratio Rank: 2
CBTA Calmar Ratio Rank: 2
CBTA Martin Ratio Rank: 2

WEEK

WEEK Risk / Return Rank: 99
WEEK Sharpe Ratio Rank: 99
WEEK Sortino Ratio Rank: 99
WEEK Omega Ratio Rank: 99
WEEK Calmar Ratio Rank: 99
WEEK Martin Ratio Rank: 99

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.

CBTA vs. WEEK - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Calamos Bitcoin 80 Series Structured Alt Protection ETF - April (CBTA) and Roundhill Weekly T-Bill ETF (WEEK). 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.

	CBTA	WEEK	Difference
Sharpe ratio: Return per unit of total volatility	-0.98	9.29	-10.27
Sortino ratio: Return per unit of downside risk	-1.33	19.14	-20.48
Omega ratio: Gain probability vs. loss probability	0.84	4.65	-3.82
Calmar ratio: Return relative to maximum drawdown	-0.78	29.49	-30.26
Martin ratio: Return relative to average drawdown	-1.42	263.82	-265.24
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

CBTA vs. WEEK - Sharpe Ratio Comparison

The current CBTA Sharpe Ratio is -0.98, which is lower than the WEEK Sharpe Ratio of 9.29. The chart below compares the historical Sharpe Ratios of CBTA and WEEK, 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

	CBTA	WEEK	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	-0.98	9.29	-10.27
Sharpe Ratio (All Time) Calculated using the full available price history	-0.47	10.05	-10.52

Drawdowns

CBTA vs. WEEK - Drawdown Comparison

The maximum CBTA drawdown since its inception was -36.74%, which is greater than WEEK's maximum drawdown of -0.13%. Use the drawdown chart below to compare losses from any high point for CBTA and WEEK.

Drawdown Indicators

	CBTA	WEEK	Difference
Max Drawdown Largest peak-to-trough decline	-36.74%	-0.13%	-36.61%
Max Drawdown (1Y) Largest decline over 1 year	-36.74%	-0.13%	-36.61%
Current Drawdown Current decline from peak	-36.33%	0.00%	-36.33%
Average Drawdown Average peak-to-trough decline	-12.99%	-0.01%	-12.98%
Ulcer Index Depth and duration of drawdowns from previous peaks	20.01%	0.01%	+20.00%

Volatility

CBTA vs. WEEK - Volatility Comparison

Calamos Bitcoin 80 Series Structured Alt Protection ETF - April (CBTA) has a higher volatility of 4.51% compared to Roundhill Weekly T-Bill ETF (WEEK) at 0.07%. This indicates that CBTA's price experiences larger fluctuations and is considered to be riskier than WEEK based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	CBTA	WEEK	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.51%	0.07%	+4.44%
Volatility (6M) Calculated over the trailing 6-month period	24.83%	0.25%	+24.58%
Volatility (1Y) Calculated over the trailing 1-year period	28.99%	0.41%	+28.58%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	27.68%	0.39%	+27.29%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	27.68%	0.39%	+27.29%

CBTA vs. WEEK - Expense Ratio Comparison

CBTA has a 0.69% expense ratio, which is higher than WEEK's 0.19% expense ratio.

Dividends

CBTA vs. WEEK - Dividend Comparison

CBTA's dividend yield for the trailing twelve months is around 1.17%, less than WEEK's 3.72% yield.

Position	TTM	2025
CBTA Calamos Bitcoin 80 Series Structured Alt Protection ETF - April	1.17%	0.89%
WEEK Roundhill Weekly T-Bill ETF	3.72%	3.27%

Frequently Asked Questions

Can I hold both CBTA and WEEK in my portfolio?

CBTA and WEEK have a correlation of -0.08, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, CBTA or WEEK?

CBTA has higher volatility (4.51%) compared to WEEK (0.07%). In terms of maximum drawdown, CBTA dropped -36.74% vs WEEK's -0.13%.

Which ETF is better, CBTA or WEEK?

On 1-year performance, WEEK leads with 3.81% vs -28.38% for CBTA. On fees, WEEK is cheaper at 0.19% per year. On volatility, WEEK has been the lower-risk option at 0.07%. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF has performed better, CBTA or WEEK?

Over the 1-year period, WEEK has performed better with a 3.81% return vs -28.38%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

Which ETF is cheaper, CBTA or WEEK?

WEEK is cheaper with a 0.19% expense ratio, compared with 0.69% for CBTA.

Which ETF pays a higher dividend yield, CBTA or WEEK?

WEEK has the higher dividend yield at 3.72%, compared with 1.17% for CBTA.

What is the main difference between CBTA and WEEK?

CBTA is categorized as Defined Outcome, while WEEK is Ultrashort Bond. They also come from different issuers: Calamos and Roundhill. Their fees differ too: 0.69% for CBTA and 0.19% for WEEK.

Which has better risk-adjusted returns?

WEEK currently has the higher Sharpe Ratio (9.29 vs -0.98), 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.