CPSO vs. BAMU

Last updated Jun 4, 2026

CPSO (Calamos S&P 500 Structured Alt Protection ETF - October) and BAMU (Brookstone Ultra-Short Bond ETF) are both exchange-traded funds - CPSO is a Defined Outcome fund actively managed by Calamos, while BAMU is a Ultrashort Bond fund actively managed by Brookstone. Both are actively managed. Over the past year, CPSO returned 7.29% vs 2.93% for BAMU. At a 0.03 correlation, their price movements are largely independent. CPSO charges 0.69%/yr vs 1.09%/yr for BAMU.

Performance

CPSO vs. BAMU - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Calamos S&P 500 Structured Alt Protection ETF - October (CPSO) and Brookstone Ultra-Short Bond ETF (BAMU). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, CPSO achieves a 2.72% return, which is significantly higher than BAMU's 1.06% return.

CPSO

• 1D: -0.02%
• 1M: 0.96%
• YTD: 2.72%
• 6M: 3.00%
• 1Y: 7.29%
• 3Y*: —
• 5Y*: —
• 10Y*: —

BAMU

• 1D: 0.02%
• 1M: 0.20%
• YTD: 1.06%
• 6M: 1.25%
• 1Y: 2.93%
• 3Y*: —
• 5Y*: —
• 10Y*: —

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

CPSO vs. BAMU - Yearly Performance Comparison

	2026 (YTD)	2025	2024
CPSO Calamos S&P 500 Structured Alt Protection ETF - October	2.72%	6.24%	0.77%
BAMU Brookstone Ultra-Short Bond ETF	1.06%	3.21%	0.88%

Correlation

The correlation between CPSO and BAMU is -0.06, 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	-0.06
Correlation (All Time) Calculated using the full available price history since Oct 2, 2024	0.03

Return for Risk

CPSO vs. BAMU — Risk / Return Rank

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

CPSO

CPSO Risk / Return Rank: 93
CPSO Sharpe Ratio Rank: 93
CPSO Sortino Ratio Rank: 96
CPSO Omega Ratio Rank: 96
CPSO Calmar Ratio Rank: 88
CPSO Martin Ratio Rank: 93

BAMU

BAMU Risk / Return Rank: 98
BAMU Sharpe Ratio Rank: 97
BAMU Sortino Ratio Rank: 98
BAMU Omega Ratio Rank: 98
BAMU Calmar Ratio Rank: 99
BAMU 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.

CPSO vs. BAMU - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Calamos S&P 500 Structured Alt Protection ETF - October (CPSO) and Brookstone Ultra-Short Bond ETF (BAMU). 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.

	CPSO	BAMU	Difference
Sharpe ratio: Return per unit of total volatility	3.42	4.98	-1.56
Sortino ratio: Return per unit of downside risk	5.54	8.77	-3.23
Omega ratio: Gain probability vs. loss probability	1.77	2.41	-0.64
Calmar ratio: Return relative to maximum drawdown	5.05	24.89	-19.84
Martin ratio: Return relative to average drawdown	25.43	97.89	-72.46
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

CPSO vs. BAMU - Sharpe Ratio Comparison

The current CPSO Sharpe Ratio is 3.42, which is lower than the BAMU Sharpe Ratio of 4.98. The chart below compares the historical Sharpe Ratios of CPSO and BAMU, 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

	CPSO	BAMU	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	3.42	4.98	-1.56
Sharpe Ratio (All Time) Calculated using the full available price history	1.96	4.14	-2.19

Drawdowns

CPSO vs. BAMU - Drawdown Comparison

The maximum CPSO drawdown since its inception was -3.23%, which is greater than BAMU's maximum drawdown of -0.36%. Use the drawdown chart below to compare losses from any high point for CPSO and BAMU.

Drawdown Indicators

	CPSO	BAMU	Difference
Max Drawdown Largest peak-to-trough decline	-3.23%	-0.36%	-2.87%
Max Drawdown (1Y) Largest decline over 1 year	-1.45%	-0.12%	-1.33%
Current Drawdown Current decline from peak	-0.02%	0.00%	-0.02%
Average Drawdown Average peak-to-trough decline	-0.33%	-0.02%	-0.31%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.29%	0.03%	+0.26%

Volatility

CPSO vs. BAMU - Volatility Comparison

Calamos S&P 500 Structured Alt Protection ETF - October (CPSO) has a higher volatility of 0.33% compared to Brookstone Ultra-Short Bond ETF (BAMU) at 0.07%. This indicates that CPSO's price experiences larger fluctuations and is considered to be riskier than BAMU based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	CPSO	BAMU	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.33%	0.07%	+0.26%
Volatility (6M) Calculated over the trailing 6-month period	1.66%	0.43%	+1.23%
Volatility (1Y) Calculated over the trailing 1-year period	2.14%	0.59%	+1.55%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	3.02%	0.87%	+2.15%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	3.02%	0.87%	+2.15%

CPSO vs. BAMU - Expense Ratio Comparison

CPSO has a 0.69% expense ratio, which is lower than BAMU's 1.09% expense ratio.

Dividends

CPSO vs. BAMU - Dividend Comparison

CPSO has not paid dividends to shareholders, while BAMU's dividend yield for the trailing twelve months is around 3.06%.

Position	TTM	2025	2024	2023
BAMU Brookstone Ultra-Short Bond ETF	3.06%	3.20%	3.97%	0.84%
CPSO Calamos S&P 500 Structured Alt Protection ETF - October	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both CPSO and BAMU in my portfolio?

CPSO and BAMU have a correlation of -0.06, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, CPSO or BAMU?

CPSO has higher volatility (0.33%) compared to BAMU (0.07%). In terms of maximum drawdown, CPSO dropped -3.23% vs BAMU's -0.36%.

Which ETF is better, CPSO or BAMU?

On 1-year performance, CPSO leads with 7.29% vs 2.93% for BAMU. On fees, CPSO is cheaper at 0.69% per year. On volatility, BAMU 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, CPSO or BAMU?

Over the 1-year period, CPSO has performed better with a 7.29% return vs 2.93%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

Which ETF is cheaper, CPSO or BAMU?

CPSO is cheaper with a 0.69% expense ratio, compared with 1.09% for BAMU.

Which ETF pays a higher dividend yield, CPSO or BAMU?

BAMU has the higher dividend yield at 3.06%, compared with 0.00% for CPSO.

What is the main difference between CPSO and BAMU?

CPSO is categorized as Defined Outcome, while BAMU is Ultrashort Bond. They also come from different issuers: Calamos and Brookstone. Their fees differ too: 0.69% for CPSO and 1.09% for BAMU.

Which has better risk-adjusted returns?

BAMU currently has the higher Sharpe Ratio (4.98 vs 3.42), 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.