PDFDX vs. RYOIX

Last updated Aug 1, 2026

PDFDX (Perkins Discovery Fund) and RYOIX (Rydex Biotechnology Fund) are both Health & Biotech Equities funds. Their 0.56 correlation means they have sometimes moved together and sometimes differently. PDFDX charges 2.50%/yr vs 1.36%/yr for RYOIX.

Performance

PDFDX vs. RYOIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Perkins Discovery Fund (PDFDX) and Rydex Biotechnology Fund (RYOIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

PDFDX

• 1D: —
• 1M: —
• 6M: —
• YTD: —
• 1Y: —
• 3Y*: —
• 5Y*: —
• 10Y*: —
• ALL TIME*: —

RYOIX

• 1D: 0.50%
• 1M: -3.93%
• 6M: 15.89%
• YTD: 18.33%
• 1Y: 50.09%
• 3Y*: 18.00%
• 5Y*: 6.19%
• 10Y*: 9.33%
• ALL TIME*: 10.91%

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

Liquidity Comparison

Position	Avg. Volume Value (2W)	Avg. Volume Value (1M)	Avg. Volume Value (3M)
RYOIX Rydex Biotechnology Fund	$0.00	$0.00	$0.00

PDFDX vs. RYOIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
PDFDX Perkins Discovery Fund	4.76%	9.94%	19.19%	10.77%	-39.93%	2.11%	62.16%	15.01%	22.19%	11.58%
RYOIX Rydex Biotechnology Fund	18.33%	30.62%	-0.95%	6.06%	-13.04%	2.05%	21.94%	30.69%	-8.94%	29.68%

Correlation

The correlation between PDFDX and RYOIX is 0.44, which is low. Their historical price movements had little consistent relationship.

	Correlation
Correlation (1Y) Focuses on recent behavior, but can change the most.	0.44
Correlation (3Y) Balances recent behavior with more history.	0.58
Correlation (5Y) Shows whether the relationship held over a longer period.	0.69
Correlation (10Y) Provides a long-term view across more market conditions.	0.68
Correlation (All Time) Calculated using the full available price history since Jan 4, 1999	0.56

The correlation between PDFDX and RYOIX shifts across timeframes, from 0.44 (1 year) to 0.69 (5 years), reflecting how their relationship changes across market environments.

Return for Risk

PDFDX vs. RYOIX — Risk / Return Rank

Compare historical risk-adjusted metric ranks over the past 12 months.

PDFDX

Risk / return metrics aren't available yet — we need at least 12 months of trading data to calculate them.

RYOIX

RYOIX Risk / Return Rank: 93
RYOIX Sharpe Ratio Rank: 94
RYOIX Sortino Ratio Rank: 92
RYOIX Omega Ratio Rank: 85
RYOIX Calmar Ratio Rank: 98
RYOIX Martin Ratio Rank: 97

The rank (0–100) uses a weighted average of the Sharpe, Sortino, Omega, Calmar, and Martin percentile ranks for the trailing 12 months. Higher means stronger historical risk-adjusted performance within the peer group.

PDFDX vs. RYOIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Perkins Discovery Fund (PDFDX) and Rydex Biotechnology Fund (RYOIX). 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.

Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.

	PDFDX	RYOIX	Difference
Sharpe ratio: Return per unit of total volatility	—	2.52	—
Sortino ratio: Return per unit of downside risk	—	3.54	—
Omega ratio: Gain probability vs. loss probability	—	1.41	—
Calmar ratio: Return relative to maximum drawdown	—	5.92	—
Martin ratio: Return relative to average drawdown	—	19.14	—

Drawdowns

Drawdown Indicators

	PDFDX	RYOIX	Difference
Max Drawdown Largest peak-to-trough decline	—	-74.43%	—
Max Drawdown (1Y) Largest decline over 1 year	—	-8.43%	—
Max Drawdown (3Y) Largest decline over 3 years	—	-23.47%	—
Max Drawdown (5Y) Largest decline over 5 years	—	-33.66%	—
Max Drawdown (10Y) Largest decline over 10 years	—	-33.66%	—
Current Drawdown Current decline from peak	—	-4.80%	—
Average Drawdown Average peak-to-trough decline	—	-27.49%	—
Ulcer Index Depth and duration of drawdowns from previous peaks	—	2.60%	—

Volatility

Volatility by Period

	PDFDX	RYOIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	—	5.73%	—
Volatility (6M) Calculated over the trailing 6-month period	—	15.28%	—
Volatility (1Y) Calculated over the trailing 1-year period	—	19.84%	—
Volatility (5Y) Calculated over the trailing 5-year period, annualized	—	21.32%	—
Volatility (10Y) Calculated over the trailing 10-year period, annualized	—	23.13%	—

PDFDX vs. RYOIX - Expense Ratio Comparison

PDFDX has a 2.50% expense ratio, which is higher than RYOIX's 1.36% expense ratio.

Dividends

PDFDX vs. RYOIX - Dividend Comparison

PDFDX's dividend yield for the trailing twelve months is around 9.34%, less than RYOIX's 10.62% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
PDFDX Perkins Discovery Fund	9.34%	4.25%	0.00%	0.00%	1.78%	31.11%	1.71%	0.00%	0.58%	0.00%	0.00%	0.00%
RYOIX Rydex Biotechnology Fund	10.62%	12.57%	14.61%	0.00%	1.29%	19.39%	7.28%	8.58%	14.11%	5.38%	0.00%	1.45%

Frequently Asked Questions

Can I hold both PDFDX and RYOIX in my portfolio?

PDFDX and RYOIX have a correlation of 0.44, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.