MIGYX vs. RCKSX

Last updated Jun 3, 2026

MIGYX (Invesco Main Street Fund Class Y) and RCKSX (Rock Oak Core Growth Fund) are both Large Cap Blend Equities funds. Over the past 10 years, MIGYX returned 12.09%/yr vs 10.87%/yr for RCKSX. Their correlation of 0.86 suggests significant overlap in exposure. MIGYX charges 0.56%/yr vs 1.25%/yr for RCKSX.

Performance

MIGYX vs. RCKSX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Invesco Main Street Fund Class Y (MIGYX) and Rock Oak Core Growth Fund (RCKSX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, MIGYX achieves a 6.08% return, which is significantly lower than RCKSX's 14.25% return. Over the past 10 years, MIGYX has outperformed RCKSX with an annualized return of 12.09%, while RCKSX has yielded a comparatively lower 10.87% annualized return.

MIGYX

• 1D: 0.12%
• 1M: 3.21%
• YTD: 6.08%
• 6M: 6.27%
• 1Y: 21.16%
• 3Y*: 18.38%
• 5Y*: 10.93%
• 10Y*: 12.09%

RCKSX

• 1D: 0.64%
• 1M: 2.23%
• YTD: 14.25%
• 6M: 14.99%
• 1Y: 21.22%
• 3Y*: 19.67%
• 5Y*: 7.36%
• 10Y*: 10.87%

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

MIGYX vs. RCKSX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
MIGYX Invesco Main Street Fund Class Y	6.08%	16.31%	23.93%	23.33%	-20.02%	27.65%	14.68%	22.67%	-8.04%	17.04%
RCKSX Rock Oak Core Growth Fund	14.25%	12.99%	15.12%	15.57%	-18.09%	9.96%	13.75%	19.05%	-2.14%	22.69%

Correlation

The correlation between MIGYX and RCKSX is 0.50, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.50
Correlation (3Y) Calculated over the trailing 3-year period	0.66
Correlation (5Y) Calculated over the trailing 5-year period	0.78
Correlation (10Y) Calculated over the trailing 10-year period	0.81
Correlation (All Time) Calculated using the full available price history since Jan 4, 2005	0.86

Over the past year, the correlation between MIGYX and RCKSX has dropped to 0.50 - well below their long-term average of 0.86, suggesting their price drivers have been diverging.

Return for Risk

MIGYX vs. RCKSX — Risk / Return Rank

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

MIGYX

MIGYX Risk / Return Rank: 51
MIGYX Sharpe Ratio Rank: 46
MIGYX Sortino Ratio Rank: 47
MIGYX Omega Ratio Rank: 45
MIGYX Calmar Ratio Rank: 56
MIGYX Martin Ratio Rank: 63

RCKSX

RCKSX Risk / Return Rank: 57
RCKSX Sharpe Ratio Rank: 39
RCKSX Sortino Ratio Rank: 40
RCKSX Omega Ratio Rank: 33
RCKSX Calmar Ratio Rank: 93
RCKSX Martin Ratio Rank: 77

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.

MIGYX vs. RCKSX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Invesco Main Street Fund Class Y (MIGYX) and Rock Oak Core Growth Fund (RCKSX). 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.

	MIGYX	RCKSX	Difference
Sharpe ratio Return per unit of total volatility	2.00	1.84	+0.16
Sortino ratio Return per unit of downside risk	2.89	2.67	+0.22
Omega ratio Gain probability vs. loss probability	1.36	1.31	+0.06
Calmar ratio Return relative to maximum drawdown	2.87	5.22	-2.36
Martin ratio Return relative to average drawdown	12.35	14.54	-2.18
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

MIGYX vs. RCKSX - Sharpe Ratio Comparison

The current MIGYX Sharpe Ratio is 2.00, which is comparable to the RCKSX Sharpe Ratio of 1.84. The chart below compares the historical Sharpe Ratios of MIGYX and RCKSX, 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

	MIGYX	RCKSX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.00	1.84	+0.16
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.66	0.47	+0.19
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.69	0.62	+0.06
Sharpe Ratio (All Time) Calculated using the full available price history	0.45	0.38	+0.07

Drawdowns

MIGYX vs. RCKSX - Drawdown Comparison

The maximum MIGYX drawdown since its inception was -56.98%, roughly equal to the maximum RCKSX drawdown of -57.88%. Use the drawdown chart below to compare losses from any high point for MIGYX and RCKSX.

Drawdown Indicators

	MIGYX	RCKSX	Difference
Max Drawdown Largest peak-to-trough decline	-56.98%	-57.88%	+0.90%
Max Drawdown (1Y) Largest decline over 1 year	-10.87%	-4.14%	-6.73%
Max Drawdown (3Y) Largest decline over 3 years	-19.88%	-18.22%	-1.66%
Max Drawdown (5Y) Largest decline over 5 years	-26.59%	-22.54%	-4.05%
Max Drawdown (10Y) Largest decline over 10 years	-35.48%	-33.10%	-2.38%
Current Drawdown Current decline from peak	-0.41%	-0.47%	+0.06%
Average Drawdown Average peak-to-trough decline	-10.61%	-9.51%	-1.10%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.52%	1.49%	+1.03%

Volatility

MIGYX vs. RCKSX - Volatility Comparison

The current volatility for Invesco Main Street Fund Class Y (MIGYX) is 2.65%, while Rock Oak Core Growth Fund (RCKSX) has a volatility of 3.00%. This indicates that MIGYX experiences smaller price fluctuations and is considered to be less risky than RCKSX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MIGYX	RCKSX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.65%	3.00%	-0.35%
Volatility (6M) Calculated over the trailing 6-month period	9.86%	8.05%	+1.81%
Volatility (1Y) Calculated over the trailing 1-year period	12.23%	11.58%	+0.65%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.91%	15.66%	+1.25%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	17.90%	17.55%	+0.35%

MIGYX vs. RCKSX - Expense Ratio Comparison

MIGYX has a 0.56% expense ratio, which is lower than RCKSX's 1.25% expense ratio.

Dividends

MIGYX vs. RCKSX - Dividend Comparison

MIGYX's dividend yield for the trailing twelve months is around 7.37%, more than RCKSX's 5.48% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MIGYX Invesco Main Street Fund Class Y	7.37%	7.82%	6.36%	7.51%	5.01%	19.63%	3.23%	0.98%	20.13%	7.80%	3.22%	14.18%
RCKSX Rock Oak Core Growth Fund	5.48%	6.26%	0.47%	0.71%	1.00%	4.31%	16.56%	3.18%	0.59%	5.91%	0.70%	3.21%

Frequently Asked Questions

Can I hold both MIGYX and RCKSX in my portfolio?

MIGYX and RCKSX have a correlation of 0.50, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, MIGYX or RCKSX?

RCKSX has higher volatility (3.00%) compared to MIGYX (2.65%). In terms of maximum drawdown, MIGYX dropped -56.98% vs RCKSX's -57.88%.

Which has better risk-adjusted returns?

MIGYX currently has the higher Sharpe Ratio (2.00 vs 1.84), 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.