WMKSX vs. OBSOX

Last updated Jul 14, 2026

WMKSX (WesMark Small Company Fund) and OBSOX (Oberweis Small-Cap Opportunities Fund) are both Small Cap Growth Equities funds. Over the past 10 years, WMKSX returned 13.47%/yr vs 18.39%/yr for OBSOX. Their correlation of 0.81 suggests significant overlap in exposure. WMKSX charges 1.24%/yr vs 1.25%/yr for OBSOX.

Performance

WMKSX vs. OBSOX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in WesMark Small Company Fund (WMKSX) and Oberweis Small-Cap Opportunities Fund (OBSOX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, WMKSX achieves a 20.75% return, which is significantly lower than OBSOX's 34.50% return. Over the past 10 years, WMKSX has underperformed OBSOX with an annualized return of 13.47%, while OBSOX has yielded a comparatively higher 18.39% annualized return.

WMKSX

• 1D: -0.79%
• 1M: 1.85%
• 6M: 14.70%
• YTD: 20.75%
• 1Y: 30.80%
• 3Y*: 23.84%
• 5Y*: 11.40%
• 10Y*: 13.47%

OBSOX

• 1D: -0.96%
• 1M: -2.25%
• 6M: 30.12%
• YTD: 34.50%
• 1Y: 51.16%
• 3Y*: 21.56%
• 5Y*: 16.10%
• 10Y*: 18.39%

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

WMKSX vs. OBSOX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
WMKSX WesMark Small Company Fund	20.75%	16.19%	22.12%	19.42%	-20.72%	22.81%	36.78%	20.32%	-13.92%	13.21%
OBSOX Oberweis Small-Cap Opportunities Fund	34.50%	14.28%	16.13%	15.81%	-11.17%	43.39%	32.52%	25.06%	-7.05%	25.55%

Correlation

The correlation between WMKSX and OBSOX is 0.75, 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	0.75
Correlation (3Y) Calculated over the trailing 3-year period	0.85
Correlation (5Y) Calculated over the trailing 5-year period	0.88
Correlation (10Y) Calculated over the trailing 10-year period	0.89
Correlation (All Time) Calculated using the full available price history since Sep 16, 1996	0.81

The correlation between WMKSX and OBSOX shifts across timeframes, from 0.75 (1 year) to 0.89 (10 years), reflecting how their relationship changes across market environments.

Return for Risk

WMKSX vs. OBSOX — Risk / Return Rank

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

WMKSX

WMKSX Risk / Return Rank: 65
WMKSX Sharpe Ratio Rank: 54
WMKSX Sortino Ratio Rank: 56
WMKSX Omega Ratio Rank: 46
WMKSX Calmar Ratio Rank: 88
WMKSX Martin Ratio Rank: 81

OBSOX

OBSOX Risk / Return Rank: 73
OBSOX Sharpe Ratio Rank: 67
OBSOX Sortino Ratio Rank: 57
OBSOX Omega Ratio Rank: 53
OBSOX Calmar Ratio Rank: 94
OBSOX Martin Ratio Rank: 93

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.

WMKSX vs. OBSOX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for WesMark Small Company Fund (WMKSX) and Oberweis Small-Cap Opportunities Fund (OBSOX). 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.

	WMKSX	OBSOX	Difference
Sharpe ratio: Return per unit of total volatility	1.64	1.81	-0.17
Sortino ratio: Return per unit of downside risk	2.37	2.40	-0.03
Omega ratio: Gain probability vs. loss probability	1.28	1.30	-0.02
Calmar ratio: Return relative to maximum drawdown	3.46	4.37	-0.92
Martin ratio: Return relative to average drawdown	11.48	15.32	-3.85

WMKSX vs. OBSOX - Sharpe Ratio Comparison

The current WMKSX Sharpe Ratio is 1.64, which is comparable to the OBSOX Sharpe Ratio of 1.81. The chart below compares the historical Sharpe Ratios of WMKSX and OBSOX, 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

WMKSX vs. OBSOX - Drawdown Comparison

The maximum WMKSX drawdown since its inception was -64.09%, smaller than the maximum OBSOX drawdown of -80.52%. Use the drawdown chart below to compare losses from any high point for WMKSX and OBSOX.

Drawdown Indicators

	WMKSX	OBSOX	Difference
Max Drawdown Largest peak-to-trough decline	-64.09%	-80.52%	+16.43%
Max Drawdown (1Y) Largest decline over 1 year	-8.50%	-11.40%	+2.90%
Max Drawdown (3Y) Largest decline over 3 years	-24.20%	-27.74%	+3.54%
Max Drawdown (5Y) Largest decline over 5 years	-39.84%	-28.65%	-11.19%
Max Drawdown (10Y) Largest decline over 10 years	-39.84%	-42.79%	+2.95%
Current Drawdown Current decline from peak	-3.24%	-5.52%	+2.28%
Average Drawdown Average peak-to-trough decline	-15.63%	-30.45%	+14.82%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.56%	3.25%	-0.69%

Volatility

WMKSX vs. OBSOX - Volatility Comparison

The current volatility for WesMark Small Company Fund (WMKSX) is 4.77%, while Oberweis Small-Cap Opportunities Fund (OBSOX) has a volatility of 9.79%. This indicates that WMKSX experiences smaller price fluctuations and is considered to be less risky than OBSOX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	WMKSX	OBSOX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.77%	9.79%	-5.02%
Volatility (6M) Calculated over the trailing 6-month period	12.45%	22.56%	-10.11%
Volatility (1Y) Calculated over the trailing 1-year period	17.90%	27.48%	-9.58%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	26.12%	25.44%	+0.68%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	23.91%	24.89%	-0.98%

WMKSX vs. OBSOX - Expense Ratio Comparison

WMKSX has a 1.24% expense ratio, which is lower than OBSOX's 1.25% expense ratio.

Dividends

WMKSX vs. OBSOX - Dividend Comparison

WMKSX's dividend yield for the trailing twelve months is around 18.97%, while OBSOX has not paid dividends to shareholders.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
OBSOX Oberweis Small-Cap Opportunities Fund	0.00%	0.00%	0.80%	0.00%	0.17%	21.88%	4.05%	3.04%	28.22%	6.36%	4.24%	11.91%
WMKSX WesMark Small Company Fund	18.97%	22.91%	4.69%	5.93%	6.23%	25.75%	8.21%	0.00%	12.53%	8.59%	5.26%	6.57%

Frequently Asked Questions

Can I hold both WMKSX and OBSOX in my portfolio?

WMKSX and OBSOX have a correlation of 0.75, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, WMKSX or OBSOX?

OBSOX has higher volatility (9.79%) compared to WMKSX (4.77%). In terms of maximum drawdown, WMKSX dropped -64.09% vs OBSOX's -80.52%.

Which has better risk-adjusted returns?

OBSOX currently has the higher Sharpe Ratio (1.81 vs 1.64), 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.