FSTSX vs. FNILX

Last updated Jun 4, 2026

FSTSX (Fidelity Series International Small Cap Fund) and FNILX (Fidelity ZERO Large Cap Index Fund) are both mutual funds - FSTSX is a Foreign Small & Mid Cap Equities fund managed by Fidelity, while FNILX is a Large Cap Blend Equities fund managed by Fidelity. Over the past 5 years, FSTSX returned 6.40%/yr vs 14.13%/yr for FNILX. A 0.70 correlation means they provide meaningful diversification when combined. FSTSX charges 0.03%/yr vs 0.00%/yr for FNILX.

Performance

FSTSX vs. FNILX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Series International Small Cap Fund (FSTSX) and Fidelity ZERO Large Cap Index Fund (FNILX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, FSTSX achieves a 7.71% return, which is significantly lower than FNILX's 11.56% return.

FSTSX

• 1D: 0.47%
• 1M: 2.77%
• YTD: 7.71%
• 6M: 10.35%
• 1Y: 18.27%
• 3Y*: 15.84%
• 5Y*: 6.40%
• 10Y*: 9.90%

FNILX

• 1D: 0.26%
• 1M: 6.04%
• YTD: 11.56%
• 6M: 11.44%
• 1Y: 28.65%
• 3Y*: 23.01%
• 5Y*: 14.13%
• 10Y*: —

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

FSTSX vs. FNILX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018
FSTSX Fidelity Series International Small Cap Fund	7.71%	27.49%	4.97%	18.36%	-26.25%	18.29%	19.61%	28.24%	-12.85%
FNILX Fidelity ZERO Large Cap Index Fund	11.56%	17.81%	25.47%	27.45%	-19.37%	26.67%	21.13%	31.79%	-13.60%

Correlation

The correlation between FSTSX and FNILX is 0.67, 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	0.67
Correlation (3Y) Calculated over the trailing 3-year period	0.64
Correlation (5Y) Calculated over the trailing 5-year period	0.69
Correlation (All Time) Calculated using the full available price history since Oct 1, 2018	0.70

The correlation between FSTSX and FNILX has been stable across timeframes, ranging from 0.64 to 0.70 - a consistent structural relationship.

Return for Risk

FSTSX vs. FNILX — Risk / Return Rank

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

FSTSX

FSTSX Risk / Return Rank: 20
FSTSX Sharpe Ratio Rank: 20
FSTSX Sortino Ratio Rank: 20
FSTSX Omega Ratio Rank: 20
FSTSX Calmar Ratio Rank: 19
FSTSX Martin Ratio Rank: 20

FNILX

FNILX Risk / Return Rank: 71
FNILX Sharpe Ratio Rank: 73
FNILX Sortino Ratio Rank: 65
FNILX Omega Ratio Rank: 64
FNILX Calmar Ratio Rank: 72
FNILX Martin Ratio Rank: 80

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.

FSTSX vs. FNILX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Series International Small Cap Fund (FSTSX) and Fidelity ZERO Large Cap Index Fund (FNILX). 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.

	FSTSX	FNILX	Difference
Sharpe ratio: Return per unit of total volatility	1.28	2.48	-1.20
Sortino ratio: Return per unit of downside risk	1.88	3.36	-1.47
Omega ratio: Gain probability vs. loss probability	1.23	1.45	-0.22
Calmar ratio: Return relative to maximum drawdown	1.59	3.28	-1.70
Martin ratio: Return relative to average drawdown	5.37	15.01	-9.64
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

FSTSX vs. FNILX - Sharpe Ratio Comparison

The current FSTSX Sharpe Ratio is 1.28, which is lower than the FNILX Sharpe Ratio of 2.48. The chart below compares the historical Sharpe Ratios of FSTSX and FNILX, 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

	FSTSX	FNILX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.28	2.48	-1.20
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.39	0.82	-0.43
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.62	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.62	0.76	-0.14

Drawdowns

FSTSX vs. FNILX - Drawdown Comparison

The maximum FSTSX drawdown since its inception was -38.91%, which is greater than FNILX's maximum drawdown of -33.76%. Use the drawdown chart below to compare losses from any high point for FSTSX and FNILX.

Drawdown Indicators

	FSTSX	FNILX	Difference
Max Drawdown Largest peak-to-trough decline	-38.91%	-33.76%	-5.15%
Max Drawdown (1Y) Largest decline over 1 year	-11.22%	-9.01%	-2.21%
Max Drawdown (3Y) Largest decline over 3 years	-14.47%	-19.08%	+4.61%
Max Drawdown (5Y) Largest decline over 5 years	-38.91%	-25.40%	-13.51%
Max Drawdown (10Y) Largest decline over 10 years	-38.91%	—	—
Current Drawdown Current decline from peak	-1.08%	0.00%	-1.08%
Average Drawdown Average peak-to-trough decline	-7.89%	-5.37%	-2.52%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.30%	1.97%	+1.33%

Volatility

FSTSX vs. FNILX - Volatility Comparison

Fidelity Series International Small Cap Fund (FSTSX) has a higher volatility of 4.43% compared to Fidelity ZERO Large Cap Index Fund (FNILX) at 2.88%. This indicates that FSTSX's price experiences larger fluctuations and is considered to be riskier than FNILX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FSTSX	FNILX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.43%	2.88%	+1.55%
Volatility (6M) Calculated over the trailing 6-month period	11.06%	8.99%	+2.07%
Volatility (1Y) Calculated over the trailing 1-year period	13.93%	11.93%	+2.00%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.42%	17.25%	-0.83%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	15.94%	20.04%	-4.10%

FSTSX vs. FNILX - Expense Ratio Comparison

FSTSX has a 0.03% expense ratio, which is higher than FNILX'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

FSTSX vs. FNILX - Dividend Comparison

FSTSX's dividend yield for the trailing twelve months is around 14.15%, more than FNILX's 0.91% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FNILX Fidelity ZERO Large Cap Index Fund	0.91%	1.01%	1.09%	1.34%	1.53%	0.95%	1.20%	1.17%	0.53%	0.00%	0.00%	0.00%
FSTSX Fidelity Series International Small Cap Fund	14.15%	15.24%	10.22%	3.34%	6.38%	13.22%	0.81%	4.27%	10.99%	6.30%	4.01%	7.32%

Frequently Asked Questions

Can I hold both FSTSX and FNILX in my portfolio?

FSTSX and FNILX have a correlation of 0.67, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, FSTSX or FNILX?

FSTSX has higher volatility (4.43%) compared to FNILX (2.88%). In terms of maximum drawdown, FSTSX dropped -38.91% vs FNILX's -33.76%.

Which has better risk-adjusted returns?

FNILX currently has the higher Sharpe Ratio (2.48 vs 1.28), 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.