CGFAX vs. MRFOX

Last updated Jul 29, 2026

CGFAX (American Funds The Growth Fund of America Class 529-A) and MRFOX (Marshfield Concentrated Opportunity Fund) are both Large Cap Growth Equities funds. Over the past 10 years, CGFAX returned 14.97%/yr vs 15.90%/yr for MRFOX. Their 0.67 correlation means they have sometimes moved together and sometimes differently. CGFAX charges 0.62%/yr vs 1.05%/yr for MRFOX.

Performance

CGFAX vs. MRFOX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Funds The Growth Fund of America Class 529-A (CGFAX) and Marshfield Concentrated Opportunity Fund (MRFOX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, CGFAX achieves a 4.27% return, which is significantly lower than MRFOX's 4.99% return. Over the past 10 years, CGFAX has underperformed MRFOX with an annualized return of 14.97%, while MRFOX has yielded a comparatively higher 15.90% annualized return.

CGFAX

• 1D: -0.38%
• 1M: -2.33%
• 6M: 2.17%
• YTD: 4.27%
• 1Y: 10.07%
• 3Y*: 19.69%
• 5Y*: 9.95%
• 10Y*: 14.97%
• ALL TIME*: 10.57%

MRFOX

• 1D: 0.98%
• 1M: 1.95%
• 6M: 4.14%
• YTD: 4.99%
• 1Y: 10.21%
• 3Y*: 13.39%
• 5Y*: 11.65%
• 10Y*: 15.90%
• ALL TIME*: 15.61%

*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)
CGFAX American Funds The Growth Fund of America Class 529-A	$0.00	$0.00	$0.00
MRFOX Marshfield Concentrated Opportunity Fund	$0.00	$0.00	$0.00

CGFAX vs. MRFOX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
CGFAX American Funds The Growth Fund of America Class 529-A	4.27%	19.69%	27.99%	37.14%	-30.76%	19.26%	37.81%	28.09%	-3.25%	26.06%
MRFOX Marshfield Concentrated Opportunity Fund	4.99%	10.05%	17.10%	17.68%	5.06%	17.71%	15.19%	36.26%	1.89%	25.92%

Correlation

The correlation between CGFAX and MRFOX is 0.21, which is low. Their historical price movements had little consistent relationship.

	Correlation
Correlation (1Y) Focuses on recent behavior, but can change the most.	0.21
Correlation (3Y) Balances recent behavior with more history.	0.44
Correlation (5Y) Shows whether the relationship held over a longer period.	0.59
Correlation (10Y) Provides a long-term view across more market conditions.	0.65
Correlation (All Time) Calculated using the full available price history since Jan 4, 2016	0.67

Over the past year, the correlation between CGFAX and MRFOX has dropped to 0.21 - well below their long-term average of 0.67, suggesting their price drivers have been diverging.

Return for Risk

CGFAX vs. MRFOX — Risk / Return Rank

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

CGFAX

CGFAX Risk / Return Rank: 16
CGFAX Sharpe Ratio Rank: 15
CGFAX Sortino Ratio Rank: 15
CGFAX Omega Ratio Rank: 16
CGFAX Calmar Ratio Rank: 15
CGFAX Martin Ratio Rank: 19

MRFOX

MRFOX Risk / Return Rank: 29
MRFOX Sharpe Ratio Rank: 28
MRFOX Sortino Ratio Rank: 30
MRFOX Omega Ratio Rank: 26
MRFOX Calmar Ratio Rank: 31
MRFOX Martin Ratio Rank: 28

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.

CGFAX vs. MRFOX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Funds The Growth Fund of America Class 529-A (CGFAX) and Marshfield Concentrated Opportunity Fund (MRFOX). 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.

	CGFAX	MRFOX	Difference
Sharpe ratio: Return per unit of total volatility	0.61	0.95	-0.34
Sortino ratio: Return per unit of downside risk	0.94	1.49	-0.54
Omega ratio: Gain probability vs. loss probability	1.12	1.17	-0.05
Calmar ratio: Return relative to maximum drawdown	0.74	1.39	-0.64
Martin ratio: Return relative to average drawdown	2.75	4.08	-1.33

CGFAX vs. MRFOX - Sharpe Ratio Comparison

The current CGFAX Sharpe Ratio is 0.61, which is lower than the MRFOX Sharpe Ratio of 0.95. The chart below compares the historical Sharpe Ratios of CGFAX and MRFOX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Drawdowns

CGFAX vs. MRFOX - Drawdown Comparison

The maximum CGFAX drawdown since its inception was -51.91%, which is greater than MRFOX's maximum drawdown of -29.10%. Use the drawdown chart below to compare losses from any high point for CGFAX and MRFOX.

Drawdown Indicators

	CGFAX	MRFOX	Difference
Max Drawdown Largest peak-to-trough decline	-51.91%	-29.10%	-22.81%
Max Drawdown (1Y) Largest decline over 1 year	-13.77%	-7.03%	-6.74%
Max Drawdown (3Y) Largest decline over 3 years	-21.58%	-7.91%	-13.67%
Max Drawdown (5Y) Largest decline over 5 years	-36.39%	-12.98%	-23.41%
Max Drawdown (10Y) Largest decline over 10 years	-36.39%	-29.10%	-7.29%
Current Drawdown Current decline from peak	-5.58%	-0.39%	-5.19%
Average Drawdown Average peak-to-trough decline	-8.57%	-2.35%	-6.22%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.72%	2.39%	+1.33%

Volatility

CGFAX vs. MRFOX - Volatility Comparison

American Funds The Growth Fund of America Class 529-A (CGFAX) and Marshfield Concentrated Opportunity Fund (MRFOX) have volatilities of 4.47% and 4.30%, respectively, indicating that both stocks experience similar levels of price fluctuations. This suggests that the risk associated with both stocks, as measured by volatility, is nearly the same. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	CGFAX	MRFOX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.47%	4.30%	+0.17%
Volatility (6M) Calculated over the trailing 6-month period	13.38%	7.79%	+5.59%
Volatility (1Y) Calculated over the trailing 1-year period	16.76%	10.28%	+6.48%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	20.54%	12.15%	+8.39%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	19.78%	14.17%	+5.61%

CGFAX vs. MRFOX - Expense Ratio Comparison

CGFAX has a 0.62% expense ratio, which is lower than MRFOX's 1.05% expense ratio.

Dividends

CGFAX vs. MRFOX - Dividend Comparison

CGFAX's dividend yield for the trailing twelve months is around 10.44%, more than MRFOX's 1.54% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
CGFAX American Funds The Growth Fund of America Class 529-A	10.44%	10.88%	9.12%	7.48%	4.09%	8.26%	4.34%	7.18%	12.03%	7.07%	6.60%	8.86%
MRFOX Marshfield Concentrated Opportunity Fund	1.54%	1.62%	4.59%	0.46%	0.35%	6.78%	2.68%	1.39%	1.94%	2.06%	0.60%	0.00%

Frequently Asked Questions

Can I hold both CGFAX and MRFOX in my portfolio?

CGFAX and MRFOX have a correlation of 0.21, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, CGFAX or MRFOX?

CGFAX has higher volatility (4.47%) compared to MRFOX (4.30%). In terms of maximum drawdown, CGFAX dropped -51.91% vs MRFOX's -29.10%.

Which has better risk-adjusted returns?

MRFOX currently has the higher Sharpe Ratio (0.95 vs 0.61), 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.