BRSJX vs. RIVSX

Last updated Jun 23, 2026

BRSJX (MFS Blended Research Small Cap Equity Fund) and RIVSX (River Oak Discovery Fund) are both Small Cap Blend Equities funds. Over the past 10 years, BRSJX returned 9.64%/yr vs 12.48%/yr for RIVSX. Their correlation of 0.90 suggests significant overlap in exposure. BRSJX charges 0.74%/yr vs 1.18%/yr for RIVSX.

Performance

BRSJX vs. RIVSX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in MFS Blended Research Small Cap Equity Fund (BRSJX) and River Oak Discovery Fund (RIVSX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, BRSJX achieves a 14.92% return, which is significantly lower than RIVSX's 34.61% return. Over the past 10 years, BRSJX has underperformed RIVSX with an annualized return of 9.64%, while RIVSX has yielded a comparatively higher 12.48% annualized return.

BRSJX

• 1D: 1.80%
• 1M: 2.48%
• YTD: 14.92%
• 6M: 11.81%
• 1Y: 31.10%
• 3Y*: 12.37%
• 5Y*: 5.99%
• 10Y*: 9.64%

RIVSX

• 1D: 1.66%
• 1M: 4.20%
• YTD: 34.61%
• 6M: 32.22%
• 1Y: 56.93%
• 3Y*: 16.93%
• 5Y*: 9.87%
• 10Y*: 12.48%

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

BRSJX vs. RIVSX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
BRSJX MFS Blended Research Small Cap Equity Fund	14.92%	5.80%	4.75%	18.84%	-18.40%	28.88%	2.09%	26.23%	-5.37%	13.22%
RIVSX River Oak Discovery Fund	34.61%	9.11%	4.42%	8.18%	-14.53%	24.78%	29.00%	30.36%	-13.72%	11.33%

Correlation

The correlation between BRSJX and RIVSX is 0.85, indicating a strong positive relationship between their price movements. Combining them offers limited diversification - they tend to fall together during downturns.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.85
Correlation (3Y) Calculated over the trailing 3-year period	0.89
Correlation (5Y) Calculated over the trailing 5-year period	0.91
Correlation (10Y) Calculated over the trailing 10-year period	0.89
Correlation (All Time) Calculated using the full available price history since Jan 4, 2016	0.90

The correlation between BRSJX and RIVSX has been stable across timeframes, ranging from 0.85 to 0.91 - a consistent structural relationship.

Return for Risk

BRSJX vs. RIVSX — Risk / Return Rank

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

BRSJX

BRSJX Risk / Return Rank: 45
BRSJX Sharpe Ratio Rank: 37
BRSJX Sortino Ratio Rank: 37
BRSJX Omega Ratio Rank: 33
BRSJX Calmar Ratio Rank: 67
BRSJX Martin Ratio Rank: 51

RIVSX

RIVSX Risk / Return Rank: 92
RIVSX Sharpe Ratio Rank: 94
RIVSX Sortino Ratio Rank: 89
RIVSX Omega Ratio Rank: 83
RIVSX Calmar Ratio Rank: 97
RIVSX Martin Ratio Rank: 96

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.

BRSJX vs. RIVSX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for MFS Blended Research Small Cap Equity Fund (BRSJX) and River Oak Discovery Fund (RIVSX). 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.

	BRSJX	RIVSX	Difference
Sharpe ratio: Return per unit of total volatility	1.63	2.98	-1.35
Sortino ratio: Return per unit of downside risk	2.36	3.98	-1.62
Omega ratio: Gain probability vs. loss probability	1.28	1.51	-0.22
Calmar ratio: Return relative to maximum drawdown	2.99	6.20	-3.21
Martin ratio: Return relative to average drawdown	9.80	21.82	-12.02

BRSJX vs. RIVSX - Sharpe Ratio Comparison

The current BRSJX Sharpe Ratio is 1.63, which is lower than the RIVSX Sharpe Ratio of 2.98. The chart below compares the historical Sharpe Ratios of BRSJX and RIVSX, 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

BRSJX vs. RIVSX - Drawdown Comparison

The maximum BRSJX drawdown since its inception was -45.20%, smaller than the maximum RIVSX drawdown of -60.61%. Use the drawdown chart below to compare losses from any high point for BRSJX and RIVSX.

Drawdown Indicators

	BRSJX	RIVSX	Difference
Max Drawdown Largest peak-to-trough decline	-45.20%	-60.61%	+15.41%
Max Drawdown (1Y) Largest decline over 1 year	-10.37%	-9.11%	-1.26%
Max Drawdown (3Y) Largest decline over 3 years	-29.05%	-24.52%	-4.53%
Max Drawdown (5Y) Largest decline over 5 years	-29.05%	-25.75%	-3.30%
Max Drawdown (10Y) Largest decline over 10 years	-45.20%	-41.45%	-3.75%
Current Drawdown Current decline from peak	-0.29%	0.00%	-0.29%
Average Drawdown Average peak-to-trough decline	-8.06%	-10.46%	+2.40%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.16%	2.58%	+0.58%

Volatility

BRSJX vs. RIVSX - Volatility Comparison

MFS Blended Research Small Cap Equity Fund (BRSJX) and River Oak Discovery Fund (RIVSX) have volatilities of 6.53% and 6.69%, 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

	BRSJX	RIVSX	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.53%	6.69%	-0.16%
Volatility (6M) Calculated over the trailing 6-month period	14.32%	13.09%	+1.23%
Volatility (1Y) Calculated over the trailing 1-year period	19.07%	18.98%	+0.09%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	22.29%	20.34%	+1.95%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	23.09%	21.95%	+1.14%

BRSJX vs. RIVSX - Expense Ratio Comparison

BRSJX has a 0.74% expense ratio, which is lower than RIVSX's 1.18% expense ratio.

Dividends

BRSJX vs. RIVSX - Dividend Comparison

BRSJX's dividend yield for the trailing twelve months is around 5.84%, more than RIVSX's 0.21% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BRSJX MFS Blended Research Small Cap Equity Fund	5.84%	6.71%	7.66%	0.78%	4.18%	12.97%	0.67%	1.83%	6.23%	3.01%	0.36%	0.00%
RIVSX River Oak Discovery Fund	0.21%	0.29%	0.00%	0.00%	0.15%	16.84%	14.54%	3.81%	17.54%	5.48%	0.00%	0.11%

Frequently Asked Questions

Can I hold both BRSJX and RIVSX in my portfolio?

BRSJX and RIVSX have a correlation of 0.85, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, BRSJX or RIVSX?

RIVSX has higher volatility (6.69%) compared to BRSJX (6.53%). In terms of maximum drawdown, BRSJX dropped -45.20% vs RIVSX's -60.61%.

Which has better risk-adjusted returns?

RIVSX currently has the higher Sharpe Ratio (2.98 vs 1.63), 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.