OILGX vs. VIDAX

Last updated Jun 4, 2026

OILGX (Optimum Large Cap Growth Fund) and VIDAX (Delaware Tax-Free Idaho Fund) are both mutual funds - OILGX is a Large Cap Growth Equities fund managed by Delaware Funds, while VIDAX is a Municipal Bonds fund managed by Delaware Funds. Over the past 10 years, OILGX returned 17.39%/yr vs 2.37%/yr for VIDAX. At a correlation of -0.06, they often move in opposite directions. OILGX charges 0.89%/yr vs 0.86%/yr for VIDAX.

Performance

OILGX vs. VIDAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Optimum Large Cap Growth Fund (OILGX) and Delaware Tax-Free Idaho Fund (VIDAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, OILGX achieves a 10.05% return, which is significantly higher than VIDAX's 2.52% return. Over the past 10 years, OILGX has outperformed VIDAX with an annualized return of 17.39%, while VIDAX has yielded a comparatively lower 2.37% annualized return.

OILGX

• 1D: -0.29%
• 1M: 7.16%
• YTD: 10.05%
• 6M: 9.10%
• 1Y: 27.94%
• 3Y*: 29.54%
• 5Y*: 14.72%
• 10Y*: 17.39%

VIDAX

• 1D: 0.29%
• 1M: 1.26%
• YTD: 2.52%
• 6M: 2.92%
• 1Y: 9.05%
• 3Y*: 4.51%
• 5Y*: 1.03%
• 10Y*: 2.37%

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

OILGX vs. VIDAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
OILGX Optimum Large Cap Growth Fund	10.05%	15.97%	49.90%	41.16%	-34.69%	17.88%	33.81%	31.34%	-0.80%	32.46%
VIDAX Delaware Tax-Free Idaho Fund	2.52%	3.78%	3.68%	6.51%	-11.90%	4.05%	4.61%	7.72%	1.27%	5.05%

Correlation

The correlation between OILGX and VIDAX is 0.13, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.13
Correlation (3Y) Calculated over the trailing 3-year period	0.11
Correlation (5Y) Calculated over the trailing 5-year period	0.11
Correlation (10Y) Calculated over the trailing 10-year period	0.05
Correlation (All Time) Calculated using the full available price history since Jul 24, 2003	-0.06

The correlation between OILGX and VIDAX shifts across timeframes, from -0.06 (all time) to 0.13 (1 year), reflecting how their relationship changes across market environments.

Return for Risk

OILGX vs. VIDAX — Risk / Return Rank

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

OILGX

OILGX Risk / Return Rank: 32
OILGX Sharpe Ratio Rank: 38
OILGX Sortino Ratio Rank: 35
OILGX Omega Ratio Rank: 35
OILGX Calmar Ratio Rank: 26
OILGX Martin Ratio Rank: 28

VIDAX

VIDAX Risk / Return Rank: 72
VIDAX Sharpe Ratio Rank: 80
VIDAX Sortino Ratio Rank: 87
VIDAX Omega Ratio Rank: 87
VIDAX Calmar Ratio Rank: 57
VIDAX Martin Ratio Rank: 50

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.

OILGX vs. VIDAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Optimum Large Cap Growth Fund (OILGX) and Delaware Tax-Free Idaho Fund (VIDAX). 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.

	OILGX	VIDAX	Difference
Sharpe ratio: Return per unit of total volatility	1.80	2.61	-0.81
Sortino ratio: Return per unit of downside risk	2.45	4.16	-1.72
Omega ratio: Gain probability vs. loss probability	1.31	1.61	-0.30
Calmar ratio: Return relative to maximum drawdown	1.88	2.88	-1.00
Martin ratio: Return relative to average drawdown	6.64	10.34	-3.70
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

OILGX vs. VIDAX - Sharpe Ratio Comparison

The current OILGX Sharpe Ratio is 1.80, which is lower than the VIDAX Sharpe Ratio of 2.61. The chart below compares the historical Sharpe Ratios of OILGX and VIDAX, 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

	OILGX	VIDAX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.80	2.61	-0.81
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.63	0.20	+0.43
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.79	0.52	+0.27
Sharpe Ratio (All Time) Calculated using the full available price history	0.59	1.07	-0.48

Drawdowns

OILGX vs. VIDAX - Drawdown Comparison

The maximum OILGX drawdown since its inception was -54.28%, which is greater than VIDAX's maximum drawdown of -17.08%. Use the drawdown chart below to compare losses from any high point for OILGX and VIDAX.

Drawdown Indicators

	OILGX	VIDAX	Difference
Max Drawdown Largest peak-to-trough decline	-54.28%	-17.08%	-37.20%
Max Drawdown (1Y) Largest decline over 1 year	-15.31%	-3.13%	-12.18%
Max Drawdown (3Y) Largest decline over 3 years	-23.75%	-8.68%	-15.07%
Max Drawdown (5Y) Largest decline over 5 years	-39.97%	-17.08%	-22.89%
Max Drawdown (10Y) Largest decline over 10 years	-39.97%	-17.08%	-22.89%
Current Drawdown Current decline from peak	-0.29%	0.00%	-0.29%
Average Drawdown Average peak-to-trough decline	-8.48%	-2.03%	-6.45%
Ulcer Index Depth and duration of drawdowns from previous peaks	4.33%	0.87%	+3.46%

Volatility

OILGX vs. VIDAX - Volatility Comparison

Optimum Large Cap Growth Fund (OILGX) has a higher volatility of 3.64% compared to Delaware Tax-Free Idaho Fund (VIDAX) at 1.39%. This indicates that OILGX's price experiences larger fluctuations and is considered to be riskier than VIDAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	OILGX	VIDAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.64%	1.39%	+2.25%
Volatility (6M) Calculated over the trailing 6-month period	12.02%	2.56%	+9.46%
Volatility (1Y) Calculated over the trailing 1-year period	16.03%	3.50%	+12.53%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	23.40%	5.20%	+18.20%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	22.04%	4.57%	+17.47%

OILGX vs. VIDAX - Expense Ratio Comparison

OILGX has a 0.89% expense ratio, which is higher than VIDAX's 0.86% expense ratio.

Dividends

OILGX vs. VIDAX - Dividend Comparison

OILGX's dividend yield for the trailing twelve months is around 12.77%, more than VIDAX's 3.41% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
OILGX Optimum Large Cap Growth Fund	12.77%	14.05%	20.62%	11.50%	4.95%	14.42%	7.72%	2.98%	14.76%	18.13%	3.68%	10.49%
VIDAX Delaware Tax-Free Idaho Fund	3.41%	4.50%	3.81%	2.93%	3.06%	2.34%	3.15%	3.95%	3.57%	3.76%	3.16%	3.17%

Frequently Asked Questions

Can I hold both OILGX and VIDAX in my portfolio?

OILGX and VIDAX have a correlation of 0.13, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, OILGX or VIDAX?

OILGX has higher volatility (3.64%) compared to VIDAX (1.39%). In terms of maximum drawdown, OILGX dropped -54.28% vs VIDAX's -17.08%.

Which has better risk-adjusted returns?

VIDAX currently has the higher Sharpe Ratio (2.61 vs 1.80), 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.