CPST vs. ZMAY

Last updated Apr 14, 2026

CPST (Calamos S&P 500 Structured Alt Protection ETF - September) and ZMAY (Innovator Equity Defined Protection ETF - 1 Yr May) are both Defined Outcome funds. CPST is passively managed, while ZMAY is actively managed. A 0.65 correlation means they provide meaningful diversification when combined. CPST charges 0.69%/yr vs 0.79%/yr for ZMAY.

Performance

CPST vs. ZMAY - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Calamos S&P 500 Structured Alt Protection ETF - September (CPST) and Innovator Equity Defined Protection ETF - 1 Yr May (ZMAY). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, CPST achieves a 1.02% return, which is significantly lower than ZMAY's 1.26% return.

CPST

• 1D: 0.13%
• 1M: 0.92%
• YTD: 1.02%
• 6M: 2.02%
• 1Y: 9.21%
• 3Y*: —
• 5Y*: —
• 10Y*: —

ZMAY

• 1D: 0.14%
• 1M: 0.70%
• YTD: 1.26%
• 6M: 2.51%
• 1Y: —
• 3Y*: —
• 5Y*: —
• 10Y*: —

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

CPST vs. ZMAY - Yearly Performance Comparison

	2026 (YTD)	2025
CPST Calamos S&P 500 Structured Alt Protection ETF - September	1.02%	7.06%
ZMAY Innovator Equity Defined Protection ETF - 1 Yr May	1.26%	4.67%

Correlation

The correlation between CPST and ZMAY is 0.65, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (All Time) Calculated using the full available price history since May 2, 2025	0.65

Return for Risk

CPST vs. ZMAY — Risk / Return Rank

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

CPST

CPST Risk / Return Rank: 94
CPST Sharpe Ratio Rank: 91
CPST Sortino Ratio Rank: 96
CPST Omega Ratio Rank: 96
CPST Calmar Ratio Rank: 92
CPST Martin Ratio Rank: 96

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.

CPST vs. ZMAY - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Calamos S&P 500 Structured Alt Protection ETF - September (CPST) and Innovator Equity Defined Protection ETF - 1 Yr May (ZMAY). 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.

	CPST	ZMAY	Difference
Sharpe ratio Return per unit of total volatility	3.40	—	—
Sortino ratio Return per unit of downside risk	5.87	—	—
Omega ratio Gain probability vs. loss probability	1.81	—	—
Calmar ratio Return relative to maximum drawdown	6.25	—	—
Martin ratio Return relative to average drawdown	30.44	—	—
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

Sharpe Ratios by Period

	CPST	ZMAY	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	3.40	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	1.82	4.22	-2.40

Drawdowns

CPST vs. ZMAY - Drawdown Comparison

The maximum CPST drawdown since its inception was -3.79%, which is greater than ZMAY's maximum drawdown of -0.39%. Use the drawdown chart below to compare losses from any high point for CPST and ZMAY.

Drawdown Indicators

	CPST	ZMAY	Difference
Max Drawdown Largest peak-to-trough decline	-3.79%	-0.39%	-3.40%
Max Drawdown (1Y) Largest decline over 1 year	-1.42%	—	—
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-0.37%	-0.05%	-0.32%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.29%	—	—

Volatility

Volatility by Period

	CPST	ZMAY	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.15%	—	—
Volatility (6M) Calculated over the trailing 6-month period	1.73%	—	—
Volatility (1Y) Calculated over the trailing 1-year period	2.73%	1.52%	+1.21%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	3.49%	1.52%	+1.97%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	3.49%	1.52%	+1.97%

CPST vs. ZMAY - Expense Ratio Comparison

CPST has a 0.69% expense ratio, which is lower than ZMAY's 0.79% expense ratio.

Dividends

CPST vs. ZMAY - Dividend Comparison

Neither CPST nor ZMAY has paid dividends to shareholders.

Tickers have no history of dividend payments