ARKX vs. IDEF

Last updated Jun 6, 2026

ARKX (ARK Space Exploration & Innovation ETF) and IDEF (iShares Defense Industrials Active ETF) are both Aerospace & Defense funds. Both are actively managed. Over the past year, ARKX returned 62.33% vs 20.41% for IDEF. Their correlation of 0.84 suggests significant overlap in exposure. ARKX charges 0.75%/yr vs 0.55%/yr for IDEF.

Performance

ARKX vs. IDEF - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in ARK Space Exploration & Innovation ETF (ARKX) and iShares Defense Industrials Active ETF (IDEF). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, ARKX achieves a 17.46% return, which is significantly higher than IDEF's 3.67% return.

ARKX

• 1D: -6.38%
• 1M: 0.65%
• YTD: 17.46%
• 6M: 19.82%
• 1Y: 62.33%
• 3Y*: 33.13%
• 5Y*: 10.39%
• 10Y*: —

IDEF

• 1D: -2.68%
• 1M: -5.87%
• YTD: 3.67%
• 6M: 7.58%
• 1Y: 20.41%
• 3Y*: —
• 5Y*: —
• 10Y*: —

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

ARKX vs. IDEF - Yearly Performance Comparison

	2026 (YTD)	2025
ARKX ARK Space Exploration & Innovation ETF	17.46%	42.90%
IDEF iShares Defense Industrials Active ETF	3.67%	23.05%

Correlation

The correlation between ARKX and IDEF is 0.84, indicating a strong positive relationship between their price movements. Combining them offers limited diversification - they tend to fall together during downturns.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.84
Correlation (All Time) Calculated using the full available price history since May 22, 2025	0.84

The correlation between ARKX and IDEF has been stable across timeframes, ranging from 0.84 to 0.84 - a consistent structural relationship.

Return for Risk

ARKX vs. IDEF — Risk / Return Rank

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

ARKX

ARKX Risk / Return Rank: 54
ARKX Sharpe Ratio Rank: 57
ARKX Sortino Ratio Rank: 52
ARKX Omega Ratio Rank: 48
ARKX Calmar Ratio Rank: 63
ARKX Martin Ratio Rank: 50

IDEF

IDEF Risk / Return Rank: 27
IDEF Sharpe Ratio Rank: 28
IDEF Sortino Ratio Rank: 28
IDEF Omega Ratio Rank: 26
IDEF Calmar Ratio Rank: 29
IDEF Martin Ratio Rank: 27

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.

ARKX vs. IDEF - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for ARK Space Exploration & Innovation ETF (ARKX) and iShares Defense Industrials Active ETF (IDEF). 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.

	ARKX	IDEF	Difference
Sharpe ratio: Return per unit of total volatility	1.89	0.96	+0.93
Sortino ratio: Return per unit of downside risk	2.45	1.45	+0.99
Omega ratio: Gain probability vs. loss probability	1.29	1.17	+0.12
Calmar ratio: Return relative to maximum drawdown	3.07	1.40	+1.67
Martin ratio: Return relative to average drawdown	8.23	3.58	+4.65
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

ARKX vs. IDEF - Sharpe Ratio Comparison

The current ARKX Sharpe Ratio is 1.89, which is higher than the IDEF Sharpe Ratio of 0.96. The chart below compares the historical Sharpe Ratios of ARKX and IDEF, 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

	ARKX	IDEF	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.89	0.96	+0.93
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.37	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.38	1.25	-0.87

Drawdowns

ARKX vs. IDEF - Drawdown Comparison

The maximum ARKX drawdown since its inception was -43.61%, which is greater than IDEF's maximum drawdown of -14.63%. Use the drawdown chart below to compare losses from any high point for ARKX and IDEF.

Drawdown Indicators

	ARKX	IDEF	Difference
Max Drawdown Largest peak-to-trough decline	-43.61%	-14.63%	-28.98%
Max Drawdown (1Y) Largest decline over 1 year	-20.42%	-14.63%	-5.79%
Max Drawdown (3Y) Largest decline over 3 years	-25.47%	—	—
Max Drawdown (5Y) Largest decline over 5 years	-43.61%	—	—
Current Drawdown Current decline from peak	-9.80%	-13.20%	+3.40%
Average Drawdown Average peak-to-trough decline	-19.97%	-3.96%	-16.01%
Ulcer Index Depth and duration of drawdowns from previous peaks	7.60%	5.71%	+1.89%

Volatility

ARKX vs. IDEF - Volatility Comparison

ARK Space Exploration & Innovation ETF (ARKX) has a higher volatility of 12.24% compared to iShares Defense Industrials Active ETF (IDEF) at 8.15%. This indicates that ARKX's price experiences larger fluctuations and is considered to be riskier than IDEF based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	ARKX	IDEF	Difference
Volatility (1M) Calculated over the trailing 1-month period	12.24%	8.15%	+4.09%
Volatility (6M) Calculated over the trailing 6-month period	25.81%	18.21%	+7.60%
Volatility (1Y) Calculated over the trailing 1-year period	33.16%	21.37%	+11.79%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	27.86%	21.22%	+6.64%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	27.55%	21.22%	+6.33%

ARKX vs. IDEF - Expense Ratio Comparison

ARKX has a 0.75% expense ratio, which is higher than IDEF's 0.55% expense ratio.

Dividends

ARKX vs. IDEF - Dividend Comparison

ARKX has not paid dividends to shareholders, while IDEF's dividend yield for the trailing twelve months is around 0.16%.

Position	TTM	2025
ARKX ARK Space Exploration & Innovation ETF	0.00%	0.00%
IDEF iShares Defense Industrials Active ETF	0.16%	0.17%

Frequently Asked Questions

Can I hold both ARKX and IDEF in my portfolio?

ARKX and IDEF have a correlation of 0.84, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, ARKX or IDEF?

ARKX has higher volatility (12.24%) compared to IDEF (8.15%). In terms of maximum drawdown, ARKX dropped -43.61% vs IDEF's -14.63%.

Which ETF is better, ARKX or IDEF?

On 1-year performance, ARKX leads with 62.33% vs 20.41% for IDEF. On fees, IDEF is cheaper at 0.55% per year. On volatility, IDEF has been the lower-risk option at 8.15%. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF has performed better, ARKX or IDEF?

Over the 1-year period, ARKX has performed better with a 62.33% return vs 20.41%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

Which ETF is cheaper, ARKX or IDEF?

IDEF is cheaper with a 0.55% expense ratio, compared with 0.75% for ARKX.

Which ETF pays a higher dividend yield, ARKX or IDEF?

IDEF has the higher dividend yield at 0.16%, compared with 0.00% for ARKX.

What is the main difference between ARKX and IDEF?

They also come from different issuers: ARK and iShares. Their fees differ too: 0.75% for ARKX and 0.55% for IDEF.

Which has better risk-adjusted returns?

ARKX currently has the higher Sharpe Ratio (1.89 vs 0.96), 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.