NBMIX vs. WBSIX

Last updated Jun 4, 2026

NBMIX (Neuberger Berman Small Cap Growth Fund) and WBSIX (William Blair Small Cap Growth Fund) are both Small Cap Growth Equities funds. Over the past 10 years, NBMIX returned 15.19%/yr vs 14.81%/yr for WBSIX. Their correlation of 0.92 suggests significant overlap in exposure. NBMIX charges 1.28%/yr vs 1.25%/yr for WBSIX.

Performance

NBMIX vs. WBSIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Neuberger Berman Small Cap Growth Fund (NBMIX) and William Blair Small Cap Growth Fund (WBSIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, NBMIX achieves a 20.21% return, which is significantly higher than WBSIX's 16.21% return. Both investments have delivered pretty close results over the past 10 years, with NBMIX having a 15.19% annualized return and WBSIX not far behind at 14.81%.

NBMIX

• 1D: 2.56%
• 1M: 6.28%
• YTD: 20.21%
• 6M: 17.81%
• 1Y: 39.38%
• 3Y*: 20.63%
• 5Y*: 8.39%
• 10Y*: 15.19%

WBSIX

• 1D: 1.44%
• 1M: 5.64%
• YTD: 16.21%
• 6M: 16.70%
• 1Y: 31.29%
• 3Y*: 19.68%
• 5Y*: 8.35%
• 10Y*: 14.81%

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

NBMIX vs. WBSIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
NBMIX Neuberger Berman Small Cap Growth Fund	20.21%	9.87%	25.90%	10.01%	-24.43%	4.16%	42.83%	34.55%	4.80%	28.16%
WBSIX William Blair Small Cap Growth Fund	16.21%	3.03%	32.88%	16.38%	-21.46%	12.64%	38.87%	22.53%	-2.08%	26.81%

Correlation

The correlation between NBMIX and WBSIX is 0.87, 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	0.87
Correlation (3Y) Calculated over the trailing 3-year period	0.91
Correlation (5Y) Calculated over the trailing 5-year period	0.94
Correlation (10Y) Calculated over the trailing 10-year period	0.92
Correlation (All Time) Calculated using the full available price history since Dec 28, 1999	0.92

The correlation between NBMIX and WBSIX has been stable across timeframes, ranging from 0.87 to 0.94 - a consistent structural relationship.

Return for Risk

NBMIX vs. WBSIX — Risk / Return Rank

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

NBMIX

NBMIX Risk / Return Rank: 36
NBMIX Sharpe Ratio Rank: 34
NBMIX Sortino Ratio Rank: 29
NBMIX Omega Ratio Rank: 30
NBMIX Calmar Ratio Rank: 42
NBMIX Martin Ratio Rank: 43

WBSIX

WBSIX Risk / Return Rank: 38
WBSIX Sharpe Ratio Rank: 34
WBSIX Sortino Ratio Rank: 33
WBSIX Omega Ratio Rank: 29
WBSIX Calmar Ratio Rank: 47
WBSIX Martin Ratio Rank: 45

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.

NBMIX vs. WBSIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Neuberger Berman Small Cap Growth Fund (NBMIX) and William Blair Small Cap Growth Fund (WBSIX). 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.

	NBMIX	WBSIX	Difference
Sharpe ratio: Return per unit of total volatility	1.67	1.67	0.00
Sortino ratio: Return per unit of downside risk	2.27	2.41	-0.14
Omega ratio: Gain probability vs. loss probability	1.28	1.28	0.00
Calmar ratio: Return relative to maximum drawdown	2.46	2.62	-0.16
Martin ratio: Return relative to average drawdown	9.11	9.46	-0.35
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

NBMIX vs. WBSIX - Sharpe Ratio Comparison

The current NBMIX Sharpe Ratio is 1.67, which is comparable to the WBSIX Sharpe Ratio of 1.67. The chart below compares the historical Sharpe Ratios of NBMIX and WBSIX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Sharpe Ratios by Period

	NBMIX	WBSIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.67	1.67	0.00
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.34	0.35	-0.01
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.62	0.65	-0.02
Sharpe Ratio (All Time) Calculated using the full available price history	0.40	0.54	-0.14

Drawdowns

NBMIX vs. WBSIX - Drawdown Comparison

The maximum NBMIX drawdown since its inception was -78.77%, which is greater than WBSIX's maximum drawdown of -62.35%. Use the drawdown chart below to compare losses from any high point for NBMIX and WBSIX.

Drawdown Indicators

	NBMIX	WBSIX	Difference
Max Drawdown Largest peak-to-trough decline	-78.77%	-62.35%	-16.42%
Max Drawdown (1Y) Largest decline over 1 year	-16.65%	-12.75%	-3.90%
Max Drawdown (3Y) Largest decline over 3 years	-29.53%	-24.76%	-4.77%
Max Drawdown (5Y) Largest decline over 5 years	-36.96%	-38.13%	+1.17%
Max Drawdown (10Y) Largest decline over 10 years	-39.55%	-39.16%	-0.39%
Current Drawdown Current decline from peak	-0.10%	0.00%	-0.10%
Average Drawdown Average peak-to-trough decline	-34.51%	-11.14%	-23.37%
Ulcer Index Depth and duration of drawdowns from previous peaks	4.48%	3.51%	+0.97%

Volatility

NBMIX vs. WBSIX - Volatility Comparison

Neuberger Berman Small Cap Growth Fund (NBMIX) has a higher volatility of 8.85% compared to William Blair Small Cap Growth Fund (WBSIX) at 5.64%. This indicates that NBMIX's price experiences larger fluctuations and is considered to be riskier than WBSIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	NBMIX	WBSIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	8.85%	5.64%	+3.21%
Volatility (6M) Calculated over the trailing 6-month period	19.44%	14.48%	+4.96%
Volatility (1Y) Calculated over the trailing 1-year period	24.51%	20.00%	+4.51%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	24.87%	23.85%	+1.02%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	24.42%	23.03%	+1.39%

NBMIX vs. WBSIX - Expense Ratio Comparison

NBMIX has a 1.28% expense ratio, which is higher than WBSIX's 1.25% expense ratio.

Dividends

NBMIX vs. WBSIX - Dividend Comparison

NBMIX's dividend yield for the trailing twelve months is around 5.60%, less than WBSIX's 6.44% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
NBMIX Neuberger Berman Small Cap Growth Fund	5.60%	6.74%	0.46%	0.00%	0.00%	18.71%	1.06%	3.98%	23.77%	1.44%	0.00%	5.92%
WBSIX William Blair Small Cap Growth Fund	6.44%	7.49%	20.14%	1.53%	3.55%	17.85%	9.73%	2.07%	12.60%	16.89%	5.42%	8.25%

Frequently Asked Questions

Can I hold both NBMIX and WBSIX in my portfolio?

NBMIX and WBSIX have a correlation of 0.87, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, NBMIX or WBSIX?

NBMIX has higher volatility (8.85%) compared to WBSIX (5.64%). In terms of maximum drawdown, NBMIX dropped -78.77% vs WBSIX's -62.35%.

Which has better risk-adjusted returns?

NBMIX currently has the higher Sharpe Ratio (1.67 vs 1.67), 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.