NESIX vs. OBSOX

Last updated Aug 4, 2026

NESIX (Needham Small Cap Growth Fund Institutional) and OBSOX (Oberweis Small-Cap Opportunities Fund) are both Small Cap Growth Equities funds. Over the past 5 years, NESIX returned 6.15%/yr vs 14.49%/yr for OBSOX. Their correlation of 0.83 means they have usually moved in the same direction. NESIX charges 1.18%/yr vs 1.25%/yr for OBSOX.

Performance

NESIX vs. OBSOX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Needham Small Cap Growth Fund Institutional (NESIX) 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, NESIX achieves a 56.00% return, which is significantly higher than OBSOX's 25.99% return.

NESIX

• 1D: 1.73%
• 1M: -8.85%
• 6M: 38.72%
• YTD: 56.00%
• 1Y: 78.30%
• 3Y*: 25.24%
• 5Y*: 6.15%
• 10Y*: —
• ALL TIME*: 17.53%

OBSOX

• 1D: -0.35%
• 1M: -6.31%
• 6M: 22.50%
• YTD: 25.99%
• 1Y: 44.55%
• 3Y*: 17.31%
• 5Y*: 14.49%
• 10Y*: 17.59%
• ALL TIME*: 9.14%

*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)
NESIX Needham Small Cap Growth Fund Institutional	$0.00	$0.00	$0.00
OBSOX Oberweis Small-Cap Opportunities Fund	$0.00	$0.00	$0.00

NESIX vs. OBSOX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
NESIX Needham Small Cap Growth Fund Institutional	56.00%	11.16%	13.47%	5.85%	-29.71%	11.36%	73.06%	55.28%	-4.87%	12.63%
OBSOX Oberweis Small-Cap Opportunities Fund	25.99%	14.28%	16.13%	15.81%	-11.17%	43.39%	32.52%	25.06%	-7.05%	25.55%

Correlation

The correlation between NESIX and OBSOX is 0.86, meaning they have usually moved in the same direction, including during past declines.

	Correlation
Correlation (1Y) Focuses on recent behavior, but can change the most.	0.86
Correlation (3Y) Balances recent behavior with more history.	0.86
Correlation (5Y) Shows whether the relationship held over a longer period.	0.86
Correlation (All Time) Calculated using the full available price history since Jan 3, 2017	0.83

The correlation between NESIX and OBSOX has been stable across timeframes, ranging from 0.83 to 0.86 - a consistent structural relationship.

Return for Risk

NESIX vs. OBSOX — Risk / Return Rank

Compare historical risk-adjusted metric ranks over the past 12 months.

NESIX

NESIX Risk / Return Rank: 83
NESIX Sharpe Ratio Rank: 87
NESIX Sortino Ratio Rank: 76
NESIX Omega Ratio Rank: 74
NESIX Calmar Ratio Rank: 88
NESIX Martin Ratio Rank: 90

OBSOX

OBSOX Risk / Return Rank: 62
OBSOX Sharpe Ratio Rank: 53
OBSOX Sortino Ratio Rank: 48
OBSOX Omega Ratio Rank: 44
OBSOX Calmar Ratio Rank: 83
OBSOX Martin Ratio Rank: 81

The rank (0–100) uses a weighted average of the Sharpe, Sortino, Omega, Calmar, and Martin percentile ranks for the trailing 12 months. Higher means stronger historical risk-adjusted performance within the peer group.

NESIX vs. OBSOX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Needham Small Cap Growth Fund Institutional (NESIX) 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.

	NESIX	OBSOX	Difference
Sharpe ratio: Return per unit of total volatility	2.17	1.49	+0.68
Sortino ratio: Return per unit of downside risk	2.68	2.06	+0.63
Omega ratio: Gain probability vs. loss probability	1.34	1.25	+0.08
Calmar ratio: Return relative to maximum drawdown	3.36	2.88	+0.48
Martin ratio: Return relative to average drawdown	12.96	10.39	+2.57

NESIX vs. OBSOX - Sharpe Ratio Comparison

The current NESIX Sharpe Ratio is 2.17, which is higher than the OBSOX Sharpe Ratio of 1.49. The chart below compares the historical Sharpe Ratios of NESIX 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

NESIX vs. OBSOX - Drawdown Comparison

The maximum NESIX drawdown since its inception was -49.61%, smaller than the maximum OBSOX drawdown of -80.52%. Use the drawdown chart below to compare losses from any high point for NESIX and OBSOX.

Drawdown Indicators

	NESIX	OBSOX	Difference
Max Drawdown Largest peak-to-trough decline	-49.61%	-80.52%	+30.91%
Max Drawdown (1Y) Largest decline over 1 year	-22.10%	-14.64%	-7.46%
Max Drawdown (3Y) Largest decline over 3 years	-35.21%	-27.74%	-7.47%
Max Drawdown (5Y) Largest decline over 5 years	-49.61%	-28.65%	-20.96%
Max Drawdown (10Y) Largest decline over 10 years	—	-42.79%	—
Current Drawdown Current decline from peak	-16.63%	-11.50%	-5.13%
Average Drawdown Average peak-to-trough decline	-14.87%	-30.41%	+15.54%
Ulcer Index Depth and duration of drawdowns from previous peaks	5.72%	4.05%	+1.67%

Volatility

NESIX vs. OBSOX - Volatility Comparison

Needham Small Cap Growth Fund Institutional (NESIX) has a higher volatility of 13.44% compared to Oberweis Small-Cap Opportunities Fund (OBSOX) at 8.97%. This indicates that NESIX's price experiences larger fluctuations and is considered to be riskier than OBSOX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	NESIX	OBSOX	Difference
Volatility (1M) Calculated over the trailing 1-month period	13.44%	8.97%	+4.47%
Volatility (6M) Calculated over the trailing 6-month period	26.18%	23.60%	+2.58%
Volatility (1Y) Calculated over the trailing 1-year period	34.35%	28.37%	+5.98%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	30.17%	25.50%	+4.67%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	26.86%	25.00%	+1.86%

NESIX vs. OBSOX - Expense Ratio Comparison

NESIX has a 1.18% expense ratio, which is lower than OBSOX's 1.25% expense ratio.

Dividends

NESIX vs. OBSOX - Dividend Comparison

Neither NESIX nor OBSOX has paid dividends to shareholders.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
NESIX Needham Small Cap Growth Fund Institutional	0.00%	0.00%	0.00%	0.00%	3.93%	23.92%	13.26%	8.25%	21.96%	8.89%	0.00%	0.00%
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%

Frequently Asked Questions

Can I hold both NESIX and OBSOX in my portfolio?

NESIX and OBSOX have a correlation of 0.86, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, NESIX or OBSOX?

NESIX has higher volatility (13.44%) compared to OBSOX (8.97%). In terms of maximum drawdown, NESIX dropped -49.61% vs OBSOX's -80.52%.

Which has better risk-adjusted returns?

NESIX currently has the higher Sharpe Ratio (2.17 vs 1.49), 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.