VIMSX vs. FZFLX

Last updated Apr 3, 2026

Compare and contrast key facts about Vanguard Mid Cap Index Fund (VIMSX) and Fidelity SAI Small-Mid Cap 500 Index Fund (FZFLX).

VIMSX is managed by Vanguard. It was launched on May 21, 1998. FZFLX is managed by Fidelity. It was launched on Aug 12, 2015.

Performance

VIMSX vs. FZFLX - Performance Comparison

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

VIMSX vs. FZFLX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
VIMSX Vanguard Mid Cap Index Fund	-0.09%	11.08%	14.52%	16.40%	-18.80%	24.36%	18.04%	30.85%	-9.35%	19.12%
FZFLX Fidelity SAI Small-Mid Cap 500 Index Fund	10.04%	10.76%	15.52%	17.75%	-15.62%	20.40%	19.78%	31.96%	-9.25%	18.41%

Returns By Period

In the year-to-date period, VIMSX achieves a -0.09% return, which is significantly lower than FZFLX's 10.04% return. Over the past 10 years, VIMSX has underperformed FZFLX with an annualized return of 10.54%, while FZFLX has yielded a comparatively higher 12.31% annualized return.

VIMSX

• 1D: 0.57%
• 1M: -3.91%
• YTD: -0.09%
• 6M: -1.20%
• 1Y: 11.74%
• 3Y*: 12.52%
• 5Y*: 6.56%
• 10Y*: 10.54%

FZFLX

• 1D: 2.07%
• 1M: -1.00%
• YTD: 10.04%
• 6M: 11.37%
• 1Y: 27.07%
• 3Y*: 16.84%
• 5Y*: 8.60%
• 10Y*: 12.31%

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

VIMSX vs. FZFLX - Expense Ratio Comparison

VIMSX has a 0.17% expense ratio, which is higher than FZFLX's 0.05% 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%.

VIMSX

Vanguard Mid Cap Index Fund

FZFLX

Fidelity SAI Small-Mid Cap 500 Index Fund

Return for Risk

VIMSX vs. FZFLX — Risk / Return Rank

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

VIMSX

VIMSX Risk / Return Rank: 27
VIMSX Sharpe Ratio Rank: 23
VIMSX Sortino Ratio Rank: 24
VIMSX Omega Ratio Rank: 24
VIMSX Calmar Ratio Rank: 26
VIMSX Martin Ratio Rank: 36

FZFLX

FZFLX Risk / Return Rank: 64
FZFLX Sharpe Ratio Rank: 56
FZFLX Sortino Ratio Rank: 57
FZFLX Omega Ratio Rank: 52
FZFLX Calmar Ratio Rank: 75
FZFLX Martin Ratio Rank: 78

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. FZFLX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard Mid Cap Index Fund (VIMSX) and Fidelity SAI Small-Mid Cap 500 Index Fund (FZFLX). 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	FZFLX	Difference
Sharpe ratio Return per unit of total volatility	0.73	1.20	-0.47
Sortino ratio Return per unit of downside risk	1.13	1.74	-0.62
Omega ratio Gain probability vs. loss probability	1.16	1.24	-0.08
Calmar ratio Return relative to maximum drawdown	1.04	2.07	-1.03
Martin ratio Return relative to average drawdown	4.74	8.86	-4.13
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. FZFLX - Sharpe Ratio Comparison

The current VIMSX Sharpe Ratio is 0.73, which is lower than the FZFLX Sharpe Ratio of 1.20. The chart below compares the historical Sharpe Ratios of VIMSX and FZFLX, offering insights into how both investments have performed under varying market conditions. These values are calculated using daily returns over the previous 12 months.

Sharpe Ratios by Period

	VIMSX	FZFLX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.73	1.20	-0.47
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.37	0.42	-0.04
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.56	0.59	-0.03
Sharpe Ratio (All Time) Calculated using the full available price history	0.46	0.55	-0.09

Correlation

The correlation between VIMSX and FZFLX is 0.96, which is considered to be high. That indicates a strong positive relationship between their price movements. Having highly-correlated positions in a portfolio may signal a lack of diversification, potentially leading to increased risk during market downturns.

Dividends

VIMSX vs. FZFLX - Dividend Comparison

VIMSX's dividend yield for the trailing twelve months is around 1.37%, less than FZFLX's 52.49% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
VIMSX Vanguard Mid Cap Index Fund	1.37%	1.03%	1.37%	1.39%	1.46%	1.00%	1.34%	1.37%	1.68%	1.24%	1.34%	1.33%
FZFLX Fidelity SAI Small-Mid Cap 500 Index Fund	52.49%	57.77%	10.20%	2.35%	79.79%	50.77%	7.19%	6.49%	7.69%	1.68%	0.93%	0.67%

Drawdowns

VIMSX vs. FZFLX - Drawdown Comparison

The maximum VIMSX drawdown since its inception was -58.96%, which is greater than FZFLX's maximum drawdown of -42.03%. Use the drawdown chart below to compare losses from any high point for VIMSX and FZFLX.

Drawdown Indicators

	VIMSX	FZFLX	Difference
Max Drawdown Largest peak-to-trough decline	-58.96%	-42.03%	-16.93%
Max Drawdown (1Y) Largest decline over 1 year	-8.25%	-10.68%	+2.43%
Max Drawdown (5Y) Largest decline over 5 years	-27.63%	-24.77%	-2.86%
Max Drawdown (10Y) Largest decline over 10 years	-39.29%	-42.03%	+2.74%
Current Drawdown Current decline from peak	-5.56%	-4.27%	-1.29%
Average Drawdown Average peak-to-trough decline	-8.12%	-5.81%	-2.31%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.80%	3.39%	-0.59%

Volatility

VIMSX vs. FZFLX - Volatility Comparison

The current volatility for Vanguard Mid Cap Index Fund (VIMSX) is 4.88%, while Fidelity SAI Small-Mid Cap 500 Index Fund (FZFLX) has a volatility of 11.08%. This indicates that VIMSX experiences smaller price fluctuations and is considered to be less risky than FZFLX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VIMSX	FZFLX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.88%	11.08%	-6.20%
Volatility (6M) Calculated over the trailing 6-month period	9.68%	16.42%	-6.74%
Volatility (1Y) Calculated over the trailing 1-year period	17.68%	24.40%	-6.72%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.66%	20.78%	-3.12%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.91%	20.91%	-2.00%