VIMSX vs. VFIAX

Last updated Jun 4, 2026

VIMSX (Vanguard Mid Cap Index Fund) and VFIAX (Vanguard 500 Index Fund Admiral Shares) are both mutual funds - VIMSX is a Mid Cap Blend Equities fund managed by Vanguard, while VFIAX is a S&P 500 fund tracking the S&P 500 Index. Over the past 10 years, VIMSX returned 11.40%/yr vs 15.63%/yr for VFIAX. Their correlation of 0.92 suggests significant overlap in exposure. VIMSX charges 0.17%/yr vs 0.04%/yr for VFIAX.

Performance

VIMSX vs. VFIAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard Mid Cap Index Fund (VIMSX) and Vanguard 500 Index Fund Admiral Shares (VFIAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, VIMSX achieves a 10.48% return, which is significantly lower than VFIAX's 11.69% return. Over the past 10 years, VIMSX has underperformed VFIAX with an annualized return of 11.40%, while VFIAX has yielded a comparatively higher 15.63% annualized return.

VIMSX

• 1D: 0.90%
• 1M: 3.66%
• YTD: 10.48%
• 6M: 10.13%
• 1Y: 18.59%
• 3Y*: 16.52%
• 5Y*: 7.88%
• 10Y*: 11.40%

VFIAX

• 1D: 0.13%
• 1M: 5.80%
• YTD: 11.69%
• 6M: 11.73%
• 1Y: 28.95%
• 3Y*: 22.72%
• 5Y*: 14.24%
• 10Y*: 15.63%

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

VIMSX vs. VFIAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
VIMSX Vanguard Mid Cap Index Fund	10.48%	11.08%	14.52%	16.40%	-18.80%	24.36%	18.04%	30.85%	-9.35%	19.12%
VFIAX Vanguard 500 Index Fund Admiral Shares	11.69%	17.83%	24.97%	26.24%	-18.16%	28.65%	18.32%	31.46%	-4.45%	21.78%

Correlation

The correlation between VIMSX and VFIAX is 0.78, 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	0.78
Correlation (3Y) Calculated over the trailing 3-year period	0.83
Correlation (5Y) Calculated over the trailing 5-year period	0.89
Correlation (10Y) Calculated over the trailing 10-year period	0.91
Correlation (All Time) Calculated using the full available price history since Nov 14, 2000	0.92

The correlation between VIMSX and VFIAX shifts across timeframes, from 0.78 (1 year) to 0.92 (all time), reflecting how their relationship changes across market environments.

Return for Risk

VIMSX vs. VFIAX — Risk / Return Rank

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

VIMSX

VIMSX Risk / Return Rank: 35
VIMSX Sharpe Ratio Rank: 31
VIMSX Sortino Ratio Rank: 30
VIMSX Omega Ratio Rank: 29
VIMSX Calmar Ratio Rank: 41
VIMSX Martin Ratio Rank: 44

VFIAX

VFIAX Risk / Return Rank: 73
VFIAX Sharpe Ratio Rank: 75
VFIAX Sortino Ratio Rank: 67
VFIAX Omega Ratio Rank: 67
VFIAX Calmar Ratio Rank: 74
VFIAX Martin Ratio Rank: 83

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.

VIMSX vs. VFIAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard Mid Cap Index Fund (VIMSX) and Vanguard 500 Index Fund Admiral Shares (VFIAX). 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.

	VIMSX	VFIAX	Difference
Sharpe ratio: Return per unit of total volatility	1.60	2.52	-0.91
Sortino ratio: Return per unit of downside risk	2.29	3.42	-1.13
Omega ratio: Gain probability vs. loss probability	1.28	1.46	-0.18
Calmar ratio: Return relative to maximum drawdown	2.42	3.35	-0.93
Martin ratio: Return relative to average drawdown	9.19	15.66	-6.47
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VIMSX vs. VFIAX - Sharpe Ratio Comparison

The current VIMSX Sharpe Ratio is 1.60, which is lower than the VFIAX Sharpe Ratio of 2.52. The chart below compares the historical Sharpe Ratios of VIMSX and VFIAX, 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

	VIMSX	VFIAX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.60	2.52	-0.91
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.45	0.85	-0.40
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.60	0.87	-0.26
Sharpe Ratio (All Time) Calculated using the full available price history	0.48	0.47	+0.01

Drawdowns

VIMSX vs. VFIAX - Drawdown Comparison

The maximum VIMSX drawdown since its inception was -58.96%, which is greater than VFIAX's maximum drawdown of -55.20%. Use the drawdown chart below to compare losses from any high point for VIMSX and VFIAX.

Drawdown Indicators

	VIMSX	VFIAX	Difference
Max Drawdown Largest peak-to-trough decline	-58.96%	-55.20%	-3.76%
Max Drawdown (1Y) Largest decline over 1 year	-8.14%	-8.90%	+0.76%
Max Drawdown (3Y) Largest decline over 3 years	-19.31%	-18.75%	-0.56%
Max Drawdown (5Y) Largest decline over 5 years	-27.63%	-24.53%	-3.10%
Max Drawdown (10Y) Largest decline over 10 years	-39.29%	-33.83%	-5.46%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-8.07%	-9.40%	+1.33%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.14%	1.90%	+0.24%

Volatility

VIMSX vs. VFIAX - Volatility Comparison

Vanguard Mid Cap Index Fund (VIMSX) has a higher volatility of 2.97% compared to Vanguard 500 Index Fund Admiral Shares (VFIAX) at 2.82%. This indicates that VIMSX's price experiences larger fluctuations and is considered to be riskier than VFIAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VIMSX	VFIAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.97%	2.82%	+0.15%
Volatility (6M) Calculated over the trailing 6-month period	9.28%	8.98%	+0.30%
Volatility (1Y) Calculated over the trailing 1-year period	12.30%	11.86%	+0.44%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.64%	16.90%	+0.74%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.93%	18.07%	+0.86%

VIMSX vs. VFIAX - Expense Ratio Comparison

VIMSX has a 0.17% expense ratio, which is higher than VFIAX's 0.04% 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

VIMSX vs. VFIAX - Dividend Comparison

VIMSX's dividend yield for the trailing twelve months is around 1.23%, more than VFIAX's 1.01% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
VFIAX Vanguard 500 Index Fund Admiral Shares	1.01%	1.12%	1.24%	1.45%	1.68%	1.24%	1.53%	1.87%	2.05%	1.78%	2.02%	2.10%
VIMSX Vanguard Mid Cap Index Fund	1.23%	1.03%	1.37%	1.39%	1.46%	1.00%	1.34%	1.37%	1.68%	1.24%	1.34%	1.33%

Frequently Asked Questions

Can I hold both VIMSX and VFIAX in my portfolio?

VIMSX and VFIAX have a correlation of 0.78, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, VIMSX or VFIAX?

VIMSX has higher volatility (2.97%) compared to VFIAX (2.82%). In terms of maximum drawdown, VIMSX dropped -58.96% vs VFIAX's -55.20%.

Which has better risk-adjusted returns?

VFIAX currently has the higher Sharpe Ratio (2.52 vs 1.60), 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.