DIAMX vs. BPIRX

Last updated Jun 24, 2026

DIAMX (Diamond Hill Long-Short Fund) and BPIRX (Boston Partners Long/Short Research Fund) are both Long-Short funds. Over the past 10 years, DIAMX returned 7.15%/yr vs 7.41%/yr for BPIRX. Their correlation of 0.82 suggests significant overlap in exposure. DIAMX charges 1.36%/yr vs 1.40%/yr for BPIRX.

Performance

DIAMX vs. BPIRX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Diamond Hill Long-Short Fund (DIAMX) and Boston Partners Long/Short Research Fund (BPIRX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, DIAMX achieves a -7.62% return, which is significantly lower than BPIRX's 5.63% return. Both investments have delivered pretty close results over the past 10 years, with DIAMX having a 7.15% annualized return and BPIRX not far ahead at 7.41%.

DIAMX

• 1D: -0.88%
• 1M: -4.30%
• YTD: -7.62%
• 6M: -7.36%
• 1Y: 3.15%
• 3Y*: 9.80%
• 5Y*: 5.41%
• 10Y*: 7.15%

BPIRX

• 1D: 0.61%
• 1M: 2.56%
• YTD: 5.63%
• 6M: 5.03%
• 1Y: 14.82%
• 3Y*: 14.06%
• 5Y*: 10.88%
• 10Y*: 7.41%

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

DIAMX vs. BPIRX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
DIAMX Diamond Hill Long-Short Fund	-7.62%	18.76%	9.93%	12.14%	-8.75%	19.04%	-0.56%	22.80%	-7.32%	5.65%
BPIRX Boston Partners Long/Short Research Fund	5.63%	14.90%	13.49%	4.75%	6.48%	23.74%	-8.25%	12.60%	-10.59%	10.10%

Correlation

The correlation between DIAMX and BPIRX is 0.55, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.55
Correlation (3Y) Calculated over the trailing 3-year period	0.66
Correlation (5Y) Calculated over the trailing 5-year period	0.73
Correlation (10Y) Calculated over the trailing 10-year period	0.79
Correlation (All Time) Calculated using the full available price history since Oct 4, 2010	0.82

Over the past year, the correlation between DIAMX and BPIRX has dropped to 0.55 - well below their long-term average of 0.82, suggesting their price drivers have been diverging.

Return for Risk

DIAMX vs. BPIRX — Risk / Return Rank

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

DIAMX

DIAMX Risk / Return Rank: 6
DIAMX Sharpe Ratio Rank: 7
DIAMX Sortino Ratio Rank: 6
DIAMX Omega Ratio Rank: 6
DIAMX Calmar Ratio Rank: 5
DIAMX Martin Ratio Rank: 6

BPIRX

BPIRX Risk / Return Rank: 46
BPIRX Sharpe Ratio Rank: 46
BPIRX Sortino Ratio Rank: 47
BPIRX Omega Ratio Rank: 45
BPIRX Calmar Ratio Rank: 43
BPIRX Martin Ratio Rank: 48

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.

DIAMX vs. BPIRX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Diamond Hill Long-Short Fund (DIAMX) and Boston Partners Long/Short Research Fund (BPIRX). 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.

	DIAMX	BPIRX	Difference
Sharpe ratio: Return per unit of total volatility	0.49	1.84	-1.35
Sortino ratio: Return per unit of downside risk	0.74	2.65	-1.91
Omega ratio: Gain probability vs. loss probability	1.09	1.33	-0.25
Calmar ratio: Return relative to maximum drawdown	0.43	2.38	-1.94
Martin ratio: Return relative to average drawdown	1.33	9.40	-8.07

DIAMX vs. BPIRX - Sharpe Ratio Comparison

The current DIAMX Sharpe Ratio is 0.49, which is lower than the BPIRX Sharpe Ratio of 1.84. The chart below compares the historical Sharpe Ratios of DIAMX and BPIRX, 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

DIAMX vs. BPIRX - Drawdown Comparison

The maximum DIAMX drawdown since its inception was -40.92%, which is greater than BPIRX's maximum drawdown of -30.59%. Use the drawdown chart below to compare losses from any high point for DIAMX and BPIRX.

Drawdown Indicators

	DIAMX	BPIRX	Difference
Max Drawdown Largest peak-to-trough decline	-40.92%	-30.59%	-10.33%
Max Drawdown (1Y) Largest decline over 1 year	-8.25%	-6.46%	-1.79%
Max Drawdown (3Y) Largest decline over 3 years	-8.61%	-15.42%	+6.81%
Max Drawdown (5Y) Largest decline over 5 years	-16.96%	-15.42%	-1.54%
Max Drawdown (10Y) Largest decline over 10 years	-31.57%	-30.59%	-0.98%
Current Drawdown Current decline from peak	-8.25%	-0.34%	-7.91%
Average Drawdown Average peak-to-trough decline	-6.84%	-3.85%	-2.99%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.68%	1.63%	+1.05%

Volatility

DIAMX vs. BPIRX - Volatility Comparison

Diamond Hill Long-Short Fund (DIAMX) and Boston Partners Long/Short Research Fund (BPIRX) have volatilities of 2.66% and 2.62%, 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

	DIAMX	BPIRX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.66%	2.62%	+0.04%
Volatility (6M) Calculated over the trailing 6-month period	5.87%	6.57%	-0.70%
Volatility (1Y) Calculated over the trailing 1-year period	7.33%	8.38%	-1.05%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	10.58%	11.45%	-0.87%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	12.94%	11.70%	+1.24%

DIAMX vs. BPIRX - Expense Ratio Comparison

DIAMX has a 1.36% expense ratio, which is lower than BPIRX's 1.40% expense ratio.

Dividends

DIAMX vs. BPIRX - Dividend Comparison

DIAMX's dividend yield for the trailing twelve months is around 1.51%, less than BPIRX's 10.08% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BPIRX Boston Partners Long/Short Research Fund	10.08%	10.65%	11.38%	11.29%	20.90%	12.51%	0.00%	2.28%	5.50%	0.00%	0.00%	3.88%
DIAMX Diamond Hill Long-Short Fund	1.51%	1.39%	9.52%	4.03%	5.07%	10.81%	0.97%	6.32%	4.94%	2.15%	3.42%	0.48%

Frequently Asked Questions

Can I hold both DIAMX and BPIRX in my portfolio?

DIAMX and BPIRX have a correlation of 0.55, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, DIAMX or BPIRX?

DIAMX has higher volatility (2.66%) compared to BPIRX (2.62%). In terms of maximum drawdown, DIAMX dropped -40.92% vs BPIRX's -30.59%.

Which has better risk-adjusted returns?

BPIRX currently has the higher Sharpe Ratio (1.84 vs 0.49), 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.