FSMAX vs. FMCSX

Last updated Jun 23, 2026

FSMAX (Fidelity Extended Market Index Fund) and FMCSX (Fidelity Mid-Cap Stock Fund) are both Mid Cap Blend Equities funds from Fidelity. Over the past 10 years, FSMAX returned 12.31%/yr vs 13.10%/yr for FMCSX. Their correlation of 0.92 suggests significant overlap in exposure. FSMAX charges 0.04%/yr vs 0.85%/yr for FMCSX.

Performance

FSMAX vs. FMCSX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Extended Market Index Fund (FSMAX) and Fidelity Mid-Cap Stock Fund (FMCSX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, FSMAX achieves a 15.56% return, which is significantly lower than FMCSX's 19.85% return. Over the past 10 years, FSMAX has underperformed FMCSX with an annualized return of 12.31%, while FMCSX has yielded a comparatively higher 13.10% annualized return.

FSMAX

• 1D: 1.67%
• 1M: 4.32%
• YTD: 15.56%
• 6M: 12.55%
• 1Y: 30.47%
• 3Y*: 19.09%
• 5Y*: 6.93%
• 10Y*: 12.31%

FMCSX

• 1D: 0.72%
• 1M: 4.53%
• YTD: 19.85%
• 6M: 17.25%
• 1Y: 34.40%
• 3Y*: 18.42%
• 5Y*: 11.91%
• 10Y*: 13.10%

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

FSMAX vs. FMCSX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
FSMAX Fidelity Extended Market Index Fund	15.56%	11.40%	16.99%	25.36%	-26.44%	12.41%	32.28%	28.01%	-9.44%	18.04%
FMCSX Fidelity Mid-Cap Stock Fund	19.85%	11.80%	14.55%	11.02%	-6.40%	28.64%	11.43%	25.39%	-6.67%	18.03%

Correlation

The correlation between FSMAX and FMCSX is 0.91, 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	0.91
Correlation (3Y) Calculated over the trailing 3-year period	0.93
Correlation (5Y) Calculated over the trailing 5-year period	0.91
Correlation (10Y) Calculated over the trailing 10-year period	0.91
Correlation (All Time) Calculated using the full available price history since Sep 8, 2011	0.92

The correlation between FSMAX and FMCSX has been stable across timeframes, ranging from 0.91 to 0.93 - a consistent structural relationship.

Return for Risk

FSMAX vs. FMCSX — Risk / Return Rank

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

FSMAX

FSMAX Risk / Return Rank: 46
FSMAX Sharpe Ratio Rank: 40
FSMAX Sortino Ratio Rank: 38
FSMAX Omega Ratio Rank: 35
FSMAX Calmar Ratio Rank: 65
FSMAX Martin Ratio Rank: 55

FMCSX

FMCSX Risk / Return Rank: 71
FMCSX Sharpe Ratio Rank: 63
FMCSX Sortino Ratio Rank: 60
FMCSX Omega Ratio Rank: 55
FMCSX Calmar Ratio Rank: 88
FMCSX Martin Ratio Rank: 88

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.

FSMAX vs. FMCSX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Extended Market Index Fund (FSMAX) and Fidelity Mid-Cap Stock Fund (FMCSX). 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.

	FSMAX	FMCSX	Difference
Sharpe ratio: Return per unit of total volatility	1.71	2.14	-0.43
Sortino ratio: Return per unit of downside risk	2.38	2.97	-0.58
Omega ratio: Gain probability vs. loss probability	1.29	1.37	-0.08
Calmar ratio: Return relative to maximum drawdown	2.96	4.05	-1.09
Martin ratio: Return relative to average drawdown	10.38	15.54	-5.16

FSMAX vs. FMCSX - Sharpe Ratio Comparison

The current FSMAX Sharpe Ratio is 1.71, which is comparable to the FMCSX Sharpe Ratio of 2.14. The chart below compares the historical Sharpe Ratios of FSMAX and FMCSX, 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

FSMAX vs. FMCSX - Drawdown Comparison

The maximum FSMAX drawdown since its inception was -50.55%, smaller than the maximum FMCSX drawdown of -62.19%. Use the drawdown chart below to compare losses from any high point for FSMAX and FMCSX.

Drawdown Indicators

	FSMAX	FMCSX	Difference
Max Drawdown Largest peak-to-trough decline	-50.55%	-62.19%	+11.64%
Max Drawdown (1Y) Largest decline over 1 year	-10.26%	-8.55%	-1.71%
Max Drawdown (3Y) Largest decline over 3 years	-26.82%	-22.33%	-4.49%
Max Drawdown (5Y) Largest decline over 5 years	-36.31%	-22.33%	-13.98%
Max Drawdown (10Y) Largest decline over 10 years	-50.55%	-40.55%	-10.00%
Current Drawdown Current decline from peak	-0.11%	-0.69%	+0.58%
Average Drawdown Average peak-to-trough decline	-12.13%	-9.34%	-2.79%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.92%	2.22%	+0.70%

Volatility

FSMAX vs. FMCSX - Volatility Comparison

Fidelity Extended Market Index Fund (FSMAX) has a higher volatility of 6.36% compared to Fidelity Mid-Cap Stock Fund (FMCSX) at 5.68%. This indicates that FSMAX's price experiences larger fluctuations and is considered to be riskier than FMCSX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FSMAX	FMCSX	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.36%	5.68%	+0.68%
Volatility (6M) Calculated over the trailing 6-month period	13.32%	12.88%	+0.44%
Volatility (1Y) Calculated over the trailing 1-year period	17.80%	16.19%	+1.61%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	22.44%	17.80%	+4.64%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	30.27%	18.63%	+11.64%

FSMAX vs. FMCSX - Expense Ratio Comparison

FSMAX has a 0.04% expense ratio, which is lower than FMCSX's 0.85% expense ratio.

Dividends

FSMAX vs. FMCSX - Dividend Comparison

FSMAX's dividend yield for the trailing twelve months is around 0.50%, less than FMCSX's 5.17% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FMCSX Fidelity Mid-Cap Stock Fund	5.17%	1.83%	8.94%	2.60%	5.44%	12.80%	6.72%	6.63%	18.48%	6.66%	8.25%	14.18%
FSMAX Fidelity Extended Market Index Fund	0.50%	0.57%	0.48%	1.17%	1.90%	7.49%	2.14%	4.30%	6.09%	5.44%	4.85%	6.34%

Frequently Asked Questions

Can I hold both FSMAX and FMCSX in my portfolio?

With a correlation of 0.91, FSMAX and FMCSX move almost identically. Holding both adds very little diversification - you're essentially doubling your position in the same market segment. Choosing one is usually more capital-efficient.

Which is riskier, FSMAX or FMCSX?

FSMAX has higher volatility (6.36%) compared to FMCSX (5.68%). In terms of maximum drawdown, FSMAX dropped -50.55% vs FMCSX's -62.19%.

Which has better risk-adjusted returns?

FMCSX currently has the higher Sharpe Ratio (2.14 vs 1.71), 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.