FMSAX vs. FSKAX

Last updated Jun 6, 2026

FMSAX (Fidelity Advisor Mortgage Securities Fund Class M) and FSKAX (Fidelity Total Market Index Fund) are both mutual funds - FMSAX is a Total Bond Market fund managed by Fidelity, while FSKAX is a Large Cap Blend Equities fund managed by Fidelity. Over the past 10 years, FMSAX returned 0.87%/yr vs 15.00%/yr for FSKAX. At a correlation of -0.03, they often move in opposite directions. FMSAX charges 0.79%/yr vs 0.01%/yr for FSKAX.

Performance

FMSAX vs. FSKAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Advisor Mortgage Securities Fund Class M (FMSAX) and Fidelity Total Market Index Fund (FSKAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, FMSAX achieves a 0.72% return, which is significantly lower than FSKAX's 11.78% return. Over the past 10 years, FMSAX has underperformed FSKAX with an annualized return of 0.87%, while FSKAX has yielded a comparatively higher 15.00% annualized return.

FMSAX

• 1D: 0.20%
• 1M: -0.11%
• YTD: 0.72%
• 6M: 1.09%
• 1Y: 6.29%
• 3Y*: 3.77%
• 5Y*: -0.34%
• 10Y*: 0.87%

FSKAX

• 1D: 0.51%
• 1M: 3.12%
• YTD: 11.78%
• 6M: 11.30%
• 1Y: 29.35%
• 3Y*: 22.42%
• 5Y*: 12.83%
• 10Y*: 15.00%

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

FMSAX vs. FSKAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
FMSAX Fidelity Advisor Mortgage Securities Fund Class M	0.72%	7.91%	0.07%	4.27%	-12.80%	-1.52%	4.05%	6.04%	0.34%	2.00%
FSKAX Fidelity Total Market Index Fund	11.78%	17.06%	23.89%	26.12%	-19.53%	25.66%	20.79%	30.92%	-5.32%	20.85%

Correlation

The correlation between FMSAX and FSKAX is 0.24, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.24
Correlation (3Y) Calculated over the trailing 3-year period	0.23
Correlation (5Y) Calculated over the trailing 5-year period	0.19
Correlation (10Y) Calculated over the trailing 10-year period	0.05
Correlation (All Time) Calculated using the full available price history since Sep 9, 2011	-0.03

The correlation between FMSAX and FSKAX shifts across timeframes, from -0.03 (all time) to 0.24 (1 year), reflecting how their relationship changes across market environments.

Return for Risk

FMSAX vs. FSKAX — Risk / Return Rank

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

FMSAX

FMSAX Risk / Return Rank: 31
FMSAX Sharpe Ratio Rank: 31
FMSAX Sortino Ratio Rank: 32
FMSAX Omega Ratio Rank: 29
FMSAX Calmar Ratio Rank: 33
FMSAX Martin Ratio Rank: 31

FSKAX

FSKAX Risk / Return Rank: 70
FSKAX Sharpe Ratio Rank: 69
FSKAX Sortino Ratio Rank: 62
FSKAX Omega Ratio Rank: 62
FSKAX Calmar Ratio Rank: 75
FSKAX 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.

FMSAX vs. FSKAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Advisor Mortgage Securities Fund Class M (FMSAX) and Fidelity Total Market Index Fund (FSKAX). 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.

	FMSAX	FSKAX	Difference
Sharpe ratio: Return per unit of total volatility	1.52	2.35	-0.84
Sortino ratio: Return per unit of downside risk	2.26	3.21	-0.95
Omega ratio: Gain probability vs. loss probability	1.27	1.42	-0.15
Calmar ratio: Return relative to maximum drawdown	2.08	3.24	-1.16
Martin ratio: Return relative to average drawdown	6.79	14.87	-8.08
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

FMSAX vs. FSKAX - Sharpe Ratio Comparison

The current FMSAX Sharpe Ratio is 1.52, which is lower than the FSKAX Sharpe Ratio of 2.35. The chart below compares the historical Sharpe Ratios of FMSAX and FSKAX, 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

	FMSAX	FSKAX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.52	2.35	-0.84
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.05	0.74	-0.79
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.17	0.82	-0.64
Sharpe Ratio (All Time) Calculated using the full available price history	0.79	0.85	-0.06

Drawdowns

FMSAX vs. FSKAX - Drawdown Comparison

The maximum FMSAX drawdown since its inception was -19.47%, smaller than the maximum FSKAX drawdown of -35.01%. Use the drawdown chart below to compare losses from any high point for FMSAX and FSKAX.

Drawdown Indicators

	FMSAX	FSKAX	Difference
Max Drawdown Largest peak-to-trough decline	-19.47%	-35.01%	+15.54%
Max Drawdown (1Y) Largest decline over 1 year	-2.88%	-8.92%	+6.04%
Max Drawdown (3Y) Largest decline over 3 years	-8.14%	-19.43%	+11.29%
Max Drawdown (5Y) Largest decline over 5 years	-19.21%	-25.39%	+6.18%
Max Drawdown (10Y) Largest decline over 10 years	-19.47%	-35.01%	+15.54%
Current Drawdown Current decline from peak	-2.69%	-0.27%	-2.42%
Average Drawdown Average peak-to-trough decline	-2.03%	-4.02%	+1.99%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.88%	1.94%	-1.06%

Volatility

FMSAX vs. FSKAX - Volatility Comparison

The current volatility for Fidelity Advisor Mortgage Securities Fund Class M (FMSAX) is 1.43%, while Fidelity Total Market Index Fund (FSKAX) has a volatility of 3.03%. This indicates that FMSAX experiences smaller price fluctuations and is considered to be less risky than FSKAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FMSAX	FSKAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.43%	3.03%	-1.60%
Volatility (6M) Calculated over the trailing 6-month period	2.77%	9.26%	-6.49%
Volatility (1Y) Calculated over the trailing 1-year period	3.99%	12.28%	-8.29%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	6.79%	17.41%	-10.62%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	5.12%	18.45%	-13.33%

FMSAX vs. FSKAX - Expense Ratio Comparison

FMSAX has a 0.79% expense ratio, which is higher than FSKAX's 0.02% expense ratio.

Dividends

FMSAX vs. FSKAX - Dividend Comparison

FMSAX's dividend yield for the trailing twelve months is around 3.55%, more than FSKAX's 0.93% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FMSAX Fidelity Advisor Mortgage Securities Fund Class M	3.55%	3.57%	3.19%	2.92%	1.13%	0.48%	2.05%	2.25%	2.22%	2.26%	2.27%	1.73%
FSKAX Fidelity Total Market Index Fund	0.93%	1.01%	1.19%	1.41%	1.62%	1.15%	1.45%	1.94%	2.54%	2.07%	2.43%	0.82%

Frequently Asked Questions

Can I hold both FMSAX and FSKAX in my portfolio?

FMSAX and FSKAX have a correlation of 0.24, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, FMSAX or FSKAX?

FSKAX has higher volatility (3.03%) compared to FMSAX (1.43%). In terms of maximum drawdown, FMSAX dropped -19.47% vs FSKAX's -35.01%.

Which has better risk-adjusted returns?

FSKAX currently has the higher Sharpe Ratio (2.35 vs 1.52), 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.