RFNBX vs. RCKSX
Compare and contrast key facts about American Funds Fundamental Investors Fund Class R2 (RFNBX) and Rock Oak Core Growth Fund (RCKSX).
RFNBX is an actively managed fund by Capital Group. It was launched on May 21, 2002. RCKSX is managed by Oak Associates. It was launched on Dec 31, 2004.
Performance
RFNBX vs. RCKSX - Performance Comparison
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RFNBX vs. RCKSX - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
RFNBX American Funds Fundamental Investors Fund Class R2 | -3.54% | 23.22% | 21.80% | 24.89% | -17.32% | 21.49% | 12.51% | 26.09% | -8.89% | 21.82% |
RCKSX Rock Oak Core Growth Fund | 7.71% | 12.99% | 15.12% | 15.57% | -18.09% | 9.96% | 13.75% | 19.05% | -2.14% | 22.69% |
Returns By Period
In the year-to-date period, RFNBX achieves a -3.54% return, which is significantly lower than RCKSX's 7.71% return. Over the past 10 years, RFNBX has outperformed RCKSX with an annualized return of 12.21%, while RCKSX has yielded a comparatively lower 10.38% annualized return.
RFNBX
- 1D
- 2.94%
- 1M
- -7.11%
- YTD
- -3.54%
- 6M
- -0.28%
- 1Y
- 22.29%
- 3Y*
- 19.58%
- 5Y*
- 11.03%
- 10Y*
- 12.21%
RCKSX
- 1D
- 1.56%
- 1M
- -1.74%
- YTD
- 7.71%
- 6M
- 8.21%
- 1Y
- 22.14%
- 3Y*
- 17.13%
- 5Y*
- 5.93%
- 10Y*
- 10.38%
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RFNBX vs. RCKSX - Expense Ratio Comparison
RFNBX has a 1.36% expense ratio, which is higher than RCKSX's 1.25% expense ratio.
Return for Risk
RFNBX vs. RCKSX — Risk / Return Rank
RFNBX
RCKSX
RFNBX vs. RCKSX - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for American Funds Fundamental Investors Fund Class R2 (RFNBX) 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.
| RFNBX | RCKSX | Difference | |
|---|---|---|---|
Sharpe ratioReturn per unit of total volatility | 1.28 | 1.40 | -0.13 |
Sortino ratioReturn per unit of downside risk | 1.92 | 2.06 | -0.14 |
Omega ratioGain probability vs. loss probability | 1.27 | 1.28 | -0.01 |
Calmar ratioReturn relative to maximum drawdown | 2.04 | 2.09 | -0.05 |
Martin ratioReturn relative to average drawdown | 8.87 | 10.93 | -2.06 |
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month. | |||
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Sharpe Ratios by Period
| RFNBX | RCKSX | Difference | |
|---|---|---|---|
Sharpe Ratio (1Y)Calculated over the trailing 1-year period | 1.28 | 1.40 | -0.13 |
Sharpe Ratio (5Y)Calculated over the trailing 5-year period | 0.66 | 0.38 | +0.29 |
Sharpe Ratio (10Y)Calculated over the trailing 10-year period | 0.69 | 0.59 | +0.10 |
Sharpe Ratio (All Time)Calculated using the full available price history | 0.56 | 0.37 | +0.20 |
Correlation
The correlation between RFNBX and RCKSX is 0.87, which is considered to be high. That indicates a strong positive relationship between their price movements. Having highly-correlated positions in a portfolio may signal a lack of diversification, potentially leading to increased risk during market downturns.
Dividends
RFNBX vs. RCKSX - Dividend Comparison
RFNBX's dividend yield for the trailing twelve months is around 8.18%, more than RCKSX's 5.81% yield.
| TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
RFNBX American Funds Fundamental Investors Fund Class R2 | 8.18% | 7.90% | 8.19% | 5.13% | 4.16% | 10.27% | 0.83% | 6.20% | 8.38% | 6.54% | 3.99% | 5.32% |
RCKSX Rock Oak Core Growth Fund | 5.81% | 6.26% | 0.47% | 0.71% | 1.00% | 4.31% | 16.56% | 3.18% | 0.59% | 5.91% | 0.70% | 3.21% |
Drawdowns
RFNBX vs. RCKSX - Drawdown Comparison
The maximum RFNBX drawdown since its inception was -53.81%, smaller than the maximum RCKSX drawdown of -57.88%. Use the drawdown chart below to compare losses from any high point for RFNBX and RCKSX.
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Drawdown Indicators
| RFNBX | RCKSX | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -53.81% | -57.88% | +4.07% |
Max Drawdown (1Y)Largest decline over 1 year | -11.37% | -11.29% | -0.08% |
Max Drawdown (5Y)Largest decline over 5 years | -25.53% | -23.50% | -2.03% |
Max Drawdown (10Y)Largest decline over 10 years | -33.96% | -33.10% | -0.86% |
Current DrawdownCurrent decline from peak | -8.15% | -1.74% | -6.41% |
Average DrawdownAverage peak-to-trough decline | -7.29% | -9.58% | +2.29% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 2.61% | 2.16% | +0.45% |
Volatility
RFNBX vs. RCKSX - Volatility Comparison
American Funds Fundamental Investors Fund Class R2 (RFNBX) has a higher volatility of 6.02% compared to Rock Oak Core Growth Fund (RCKSX) at 3.72%. This indicates that RFNBX's price experiences larger fluctuations and is considered to be riskier than RCKSX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
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Volatility by Period
| RFNBX | RCKSX | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 6.02% | 3.72% | +2.30% |
Volatility (6M)Calculated over the trailing 6-month period | 11.03% | 8.88% | +2.15% |
Volatility (1Y)Calculated over the trailing 1-year period | 18.15% | 16.40% | +1.75% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 16.73% | 15.78% | +0.95% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 17.68% | 17.59% | +0.09% |