BWBIX vs. FDFIX

Last updated Jun 23, 2026

BWBIX (Baron WealthBuilder Fund) and FDFIX (Fidelity Flex 500 Index Fund) are both mutual funds - BWBIX is a Diversified Portfolio fund managed by Baron Capital Group, Inc., while FDFIX is a Large Cap Blend Equities fund tracking the Fidelity U.S. Large Cap Index. Over the past 5 years, BWBIX returned 4.87%/yr vs 14.02%/yr for FDFIX. Their correlation of 0.88 suggests significant overlap in exposure. BWBIX charges 0.05%/yr vs 0.00%/yr for FDFIX.

Performance

BWBIX vs. FDFIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Baron WealthBuilder Fund (BWBIX) and Fidelity Flex 500 Index Fund (FDFIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, BWBIX achieves a 5.25% return, which is significantly lower than FDFIX's 10.05% return.

BWBIX

• 1D: 0.40%
• 1M: 6.58%
• YTD: 5.25%
• 6M: 3.40%
• 1Y: 17.58%
• 3Y*: 14.21%
• 5Y*: 4.87%
• 10Y*: —

FDFIX

• 1D: 1.14%
• 1M: 0.69%
• YTD: 10.05%
• 6M: 9.52%
• 1Y: 26.74%
• 3Y*: 20.85%
• 5Y*: 14.02%
• 10Y*: —

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

BWBIX vs. FDFIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018
BWBIX Baron WealthBuilder Fund	5.25%	10.23%	19.62%	25.77%	-32.58%	14.76%	62.85%	36.41%	-12.02%
FDFIX Fidelity Flex 500 Index Fund	10.05%	17.59%	25.06%	26.27%	-18.10%	28.69%	18.46%	31.47%	-6.52%

Correlation

The correlation between BWBIX and FDFIX is 0.79, 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	0.79
Correlation (3Y) Calculated over the trailing 3-year period	0.86
Correlation (5Y) Calculated over the trailing 5-year period	0.88
Correlation (All Time) Calculated using the full available price history since May 21, 2018	0.88

The correlation between BWBIX and FDFIX has been stable across timeframes, ranging from 0.79 to 0.88 - a consistent structural relationship.

Return for Risk

BWBIX vs. FDFIX — Risk / Return Rank

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

BWBIX

BWBIX Risk / Return Rank: 20
BWBIX Sharpe Ratio Rank: 18
BWBIX Sortino Ratio Rank: 21
BWBIX Omega Ratio Rank: 19
BWBIX Calmar Ratio Rank: 19
BWBIX Martin Ratio Rank: 21

FDFIX

FDFIX Risk / Return Rank: 63
FDFIX Sharpe Ratio Rank: 61
FDFIX Sortino Ratio Rank: 55
FDFIX Omega Ratio Rank: 57
FDFIX Calmar Ratio Rank: 65
FDFIX 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.

BWBIX vs. FDFIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Baron WealthBuilder Fund (BWBIX) and Fidelity Flex 500 Index Fund (FDFIX). 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.

	BWBIX	FDFIX	Difference
Sharpe ratio: Return per unit of total volatility	1.13	2.12	-0.98
Sortino ratio: Return per unit of downside risk	1.80	2.86	-1.06
Omega ratio: Gain probability vs. loss probability	1.21	1.38	-0.17
Calmar ratio: Return relative to maximum drawdown	1.49	2.97	-1.48
Martin ratio: Return relative to average drawdown	4.90	13.11	-8.22

BWBIX vs. FDFIX - Sharpe Ratio Comparison

The current BWBIX Sharpe Ratio is 1.13, which is lower than the FDFIX Sharpe Ratio of 2.12. The chart below compares the historical Sharpe Ratios of BWBIX and FDFIX, 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

BWBIX vs. FDFIX - Drawdown Comparison

The maximum BWBIX drawdown since its inception was -39.14%, which is greater than FDFIX's maximum drawdown of -33.77%. Use the drawdown chart below to compare losses from any high point for BWBIX and FDFIX.

Drawdown Indicators

	BWBIX	FDFIX	Difference
Max Drawdown Largest peak-to-trough decline	-39.14%	-33.77%	-5.37%
Max Drawdown (1Y) Largest decline over 1 year	-11.65%	-8.99%	-2.66%
Max Drawdown (3Y) Largest decline over 3 years	-21.59%	-18.76%	-2.83%
Max Drawdown (5Y) Largest decline over 5 years	-39.14%	-24.51%	-14.63%
Current Drawdown Current decline from peak	-1.72%	-1.33%	-0.39%
Average Drawdown Average peak-to-trough decline	-11.66%	-4.56%	-7.10%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.54%	2.03%	+1.51%

Volatility

BWBIX vs. FDFIX - Volatility Comparison

Baron WealthBuilder Fund (BWBIX) has a higher volatility of 6.36% compared to Fidelity Flex 500 Index Fund (FDFIX) at 4.90%. This indicates that BWBIX's price experiences larger fluctuations and is considered to be riskier than FDFIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	BWBIX	FDFIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.36%	4.90%	+1.46%
Volatility (6M) Calculated over the trailing 6-month period	11.29%	10.00%	+1.29%
Volatility (1Y) Calculated over the trailing 1-year period	15.32%	12.61%	+2.71%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	21.21%	17.05%	+4.16%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	23.16%	18.60%	+4.56%

BWBIX vs. FDFIX - Expense Ratio Comparison

BWBIX has a 0.05% expense ratio, which is higher than FDFIX's 0.00% expense ratio. However, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

BWBIX vs. FDFIX - Dividend Comparison

BWBIX's dividend yield for the trailing twelve months is around 7.23%, more than FDFIX's 1.04% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017
BWBIX Baron WealthBuilder Fund	7.23%	7.61%	0.77%	0.06%	3.21%	3.75%	1.24%	3.51%	0.14%	0.00%
FDFIX Fidelity Flex 500 Index Fund	1.04%	1.11%	1.26%	1.48%	1.70%	1.27%	1.52%	1.78%	2.16%	0.50%

Frequently Asked Questions

Can I hold both BWBIX and FDFIX in my portfolio?

BWBIX and FDFIX have a correlation of 0.79, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, BWBIX or FDFIX?

BWBIX has higher volatility (6.36%) compared to FDFIX (4.90%). In terms of maximum drawdown, BWBIX dropped -39.14% vs FDFIX's -33.77%.

Which has better risk-adjusted returns?

FDFIX currently has the higher Sharpe Ratio (2.12 vs 1.13), 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.