NEEGX vs. VMFGX

Last updated Jun 24, 2026

NEEGX (Needham Growth Fund) and VMFGX (Vanguard S&P Mid-Cap 400 Growth Index Fund Institutional Shares) are both Mid Cap Growth Equities funds. Over the past 10 years, NEEGX returned 17.07%/yr vs 12.18%/yr for VMFGX. Their correlation of 0.85 suggests significant overlap in exposure. NEEGX charges 1.78%/yr vs 0.08%/yr for VMFGX.

Performance

NEEGX vs. VMFGX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Needham Growth Fund (NEEGX) and Vanguard S&P Mid-Cap 400 Growth Index Fund Institutional Shares (VMFGX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, NEEGX achieves a 65.21% return, which is significantly higher than VMFGX's 20.49% return. Over the past 10 years, NEEGX has outperformed VMFGX with an annualized return of 17.07%, while VMFGX has yielded a comparatively lower 12.18% annualized return.

NEEGX

• 1D: 1.92%
• 1M: 12.74%
• YTD: 65.21%
• 6M: 61.80%
• 1Y: 99.86%
• 3Y*: 30.16%
• 5Y*: 15.00%
• 10Y*: 17.07%

VMFGX

• 1D: 0.63%
• 1M: 4.19%
• YTD: 20.49%
• 6M: 17.90%
• 1Y: 31.74%
• 3Y*: 18.43%
• 5Y*: 8.89%
• 10Y*: 12.18%

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

NEEGX vs. VMFGX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
NEEGX Needham Growth Fund	65.21%	8.76%	14.45%	26.85%	-33.57%	27.63%	41.73%	42.33%	-10.56%	8.33%
VMFGX Vanguard S&P Mid-Cap 400 Growth Index Fund Institutional Shares	20.49%	7.43%	15.86%	17.42%	-18.99%	18.83%	22.61%	26.20%	-10.39%	19.87%

Correlation

The correlation between NEEGX and VMFGX is 0.83, 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	0.83
Correlation (3Y) Calculated over the trailing 3-year period	0.81
Correlation (5Y) Calculated over the trailing 5-year period	0.85
Correlation (10Y) Calculated over the trailing 10-year period	0.85
Correlation (All Time) Calculated using the full available price history since Jan 3, 2012	0.85

The correlation between NEEGX and VMFGX has been stable across timeframes, ranging from 0.81 to 0.85 - a consistent structural relationship.

Return for Risk

NEEGX vs. VMFGX — Risk / Return Rank

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

NEEGX

NEEGX Risk / Return Rank: 93
NEEGX Sharpe Ratio Rank: 98
NEEGX Sortino Ratio Rank: 88
NEEGX Omega Ratio Rank: 84
NEEGX Calmar Ratio Rank: 98
NEEGX Martin Ratio Rank: 97

VMFGX

VMFGX Risk / Return Rank: 58
VMFGX Sharpe Ratio Rank: 48
VMFGX Sortino Ratio Rank: 47
VMFGX Omega Ratio Rank: 44
VMFGX Calmar Ratio Rank: 77
VMFGX Martin Ratio Rank: 74

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.

NEEGX vs. VMFGX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Needham Growth Fund (NEEGX) and Vanguard S&P Mid-Cap 400 Growth Index Fund Institutional Shares (VMFGX). 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.

	NEEGX	VMFGX	Difference
Sharpe ratio: Return per unit of total volatility	3.45	1.89	+1.55
Sortino ratio: Return per unit of downside risk	3.92	2.68	+1.24
Omega ratio: Gain probability vs. loss probability	1.52	1.33	+0.19
Calmar ratio: Return relative to maximum drawdown	7.51	3.32	+4.19
Martin ratio: Return relative to average drawdown	25.00	13.13	+11.87

NEEGX vs. VMFGX - Sharpe Ratio Comparison

The current NEEGX Sharpe Ratio is 3.45, which is higher than the VMFGX Sharpe Ratio of 1.89. The chart below compares the historical Sharpe Ratios of NEEGX and VMFGX, 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

NEEGX vs. VMFGX - Drawdown Comparison

The maximum NEEGX drawdown since its inception was -53.60%, which is greater than VMFGX's maximum drawdown of -39.15%. Use the drawdown chart below to compare losses from any high point for NEEGX and VMFGX.

Drawdown Indicators

	NEEGX	VMFGX	Difference
Max Drawdown Largest peak-to-trough decline	-53.60%	-39.15%	-14.45%
Max Drawdown (1Y) Largest decline over 1 year	-13.27%	-9.91%	-3.36%
Max Drawdown (3Y) Largest decline over 3 years	-38.66%	-25.45%	-13.21%
Max Drawdown (5Y) Largest decline over 5 years	-43.35%	-29.25%	-14.10%
Max Drawdown (10Y) Largest decline over 10 years	-43.35%	-39.15%	-4.20%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-10.88%	-5.69%	-5.19%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.98%	2.50%	+1.48%

Volatility

NEEGX vs. VMFGX - Volatility Comparison

Needham Growth Fund (NEEGX) has a higher volatility of 12.90% compared to Vanguard S&P Mid-Cap 400 Growth Index Fund Institutional Shares (VMFGX) at 5.57%. This indicates that NEEGX's price experiences larger fluctuations and is considered to be riskier than VMFGX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	NEEGX	VMFGX	Difference
Volatility (1M) Calculated over the trailing 1-month period	12.90%	5.57%	+7.33%
Volatility (6M) Calculated over the trailing 6-month period	22.94%	13.68%	+9.26%
Volatility (1Y) Calculated over the trailing 1-year period	28.97%	17.42%	+11.55%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	28.72%	20.69%	+8.03%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	25.53%	21.10%	+4.43%

NEEGX vs. VMFGX - Expense Ratio Comparison

NEEGX has a 1.78% expense ratio, which is higher than VMFGX's 0.08% expense ratio.

Dividends

NEEGX vs. VMFGX - Dividend Comparison

NEEGX's dividend yield for the trailing twelve months is around 4.58%, more than VMFGX's 0.58% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
NEEGX Needham Growth Fund	4.58%	7.57%	3.92%	0.00%	1.78%	6.92%	5.73%	11.31%	17.79%	9.70%	4.22%	6.74%
VMFGX Vanguard S&P Mid-Cap 400 Growth Index Fund Institutional Shares	0.58%	0.70%	0.84%	1.21%	1.12%	0.53%	0.79%	1.22%	1.18%	0.93%	1.14%	1.14%

Frequently Asked Questions

Can I hold both NEEGX and VMFGX in my portfolio?

NEEGX and VMFGX have a correlation of 0.83, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, NEEGX or VMFGX?

NEEGX has higher volatility (12.90%) compared to VMFGX (5.57%). In terms of maximum drawdown, NEEGX dropped -53.60% vs VMFGX's -39.15%.

Which has better risk-adjusted returns?

NEEGX currently has the higher Sharpe Ratio (3.45 vs 1.89), 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.