FAOSX vs. BIGIX

Last updated Jun 23, 2026

FAOSX (Fidelity Advisor Overseas Fund Class Z) and BIGIX (William Blair International Growth Fund Class I) are both Foreign Large Cap Equities funds. Over the past 5 years, FAOSX returned 3.89%/yr vs 3.65%/yr for BIGIX. Their correlation of 0.87 suggests significant overlap in exposure. FAOSX charges 1.02%/yr vs 0.90%/yr for BIGIX.

Performance

FAOSX vs. BIGIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Advisor Overseas Fund Class Z (FAOSX) and William Blair International Growth Fund Class I (BIGIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

FAOSX

• 1D: 0.00%
• 1M: 0.00%
• YTD: 0.00%
• 6M: 0.00%
• 1Y: 0.31%
• 3Y*: 8.01%
• 5Y*: 3.89%
• 10Y*: —

BIGIX

• 1D: 1.78%
• 1M: 4.55%
• YTD: 17.77%
• 6M: 18.56%
• 1Y: 27.98%
• 3Y*: 13.26%
• 5Y*: 3.65%
• 10Y*: 8.91%

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

FAOSX vs. BIGIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
FAOSX Fidelity Advisor Overseas Fund Class Z	0.00%	15.36%	5.06%	20.52%	-24.31%	19.42%	15.17%	27.96%	-14.73%	26.25%
BIGIX William Blair International Growth Fund Class I	17.77%	18.17%	2.38%	15.43%	-28.46%	8.95%	32.01%	30.66%	-17.71%	24.63%

Correlation

The correlation between FAOSX and BIGIX is 0.45, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.45
Correlation (3Y) Calculated over the trailing 3-year period	0.77
Correlation (5Y) Calculated over the trailing 5-year period	0.86
Correlation (All Time) Calculated using the full available price history since Feb 1, 2017	0.87

Over the past year, the correlation between FAOSX and BIGIX has dropped to 0.45 - well below their long-term average of 0.87, suggesting their price drivers have been diverging.

Return for Risk

FAOSX vs. BIGIX — Risk / Return Rank

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

FAOSX

FAOSX Risk / Return Rank: 2
FAOSX Sharpe Ratio Rank: 3
FAOSX Sortino Ratio Rank: 2
FAOSX Omega Ratio Rank: 2
FAOSX Calmar Ratio Rank: 2
FAOSX Martin Ratio Rank: 3

BIGIX

BIGIX Risk / Return Rank: 38
BIGIX Sharpe Ratio Rank: 38
BIGIX Sortino Ratio Rank: 35
BIGIX Omega Ratio Rank: 44
BIGIX Calmar Ratio Rank: 34
BIGIX Martin Ratio Rank: 37

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.

FAOSX vs. BIGIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Advisor Overseas Fund Class Z (FAOSX) and William Blair International Growth Fund Class I (BIGIX). 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.

	FAOSX	BIGIX	Difference
Sharpe ratio: Return per unit of total volatility	-0.05	1.66	-1.71
Sortino ratio: Return per unit of downside risk	-0.01	2.30	-2.30
Omega ratio: Gain probability vs. loss probability	1.00	1.33	-0.33
Calmar ratio: Return relative to maximum drawdown	-0.06	2.08	-2.14
Martin ratio: Return relative to average drawdown	-0.09	7.75	-7.85

FAOSX vs. BIGIX - Sharpe Ratio Comparison

The current FAOSX Sharpe Ratio is -0.05, which is lower than the BIGIX Sharpe Ratio of 1.66. The chart below compares the historical Sharpe Ratios of FAOSX and BIGIX, 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

FAOSX vs. BIGIX - Drawdown Comparison

The maximum FAOSX drawdown since its inception was -36.24%, smaller than the maximum BIGIX drawdown of -65.22%. Use the drawdown chart below to compare losses from any high point for FAOSX and BIGIX.

Drawdown Indicators

	FAOSX	BIGIX	Difference
Max Drawdown Largest peak-to-trough decline	-36.24%	-65.22%	+28.98%
Max Drawdown (1Y) Largest decline over 1 year	-7.26%	-13.21%	+5.95%
Max Drawdown (3Y) Largest decline over 3 years	-13.96%	-17.09%	+3.13%
Max Drawdown (5Y) Largest decline over 5 years	-36.24%	-41.03%	+4.79%
Max Drawdown (10Y) Largest decline over 10 years	—	-41.03%	—
Current Drawdown Current decline from peak	-5.86%	0.00%	-5.86%
Average Drawdown Average peak-to-trough decline	-7.92%	-17.14%	+9.22%
Ulcer Index Depth and duration of drawdowns from previous peaks	4.13%	3.53%	+0.60%

Volatility

FAOSX vs. BIGIX - Volatility Comparison

The current volatility for Fidelity Advisor Overseas Fund Class Z (FAOSX) is 0.00%, while William Blair International Growth Fund Class I (BIGIX) has a volatility of 7.60%. This indicates that FAOSX experiences smaller price fluctuations and is considered to be less risky than BIGIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FAOSX	BIGIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.00%	7.60%	-7.60%
Volatility (6M) Calculated over the trailing 6-month period	3.63%	14.57%	-10.94%
Volatility (1Y) Calculated over the trailing 1-year period	8.76%	16.52%	-7.76%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.70%	16.98%	-0.28%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	16.64%	17.33%	-0.69%

FAOSX vs. BIGIX - Expense Ratio Comparison

FAOSX has a 1.02% expense ratio, which is higher than BIGIX's 0.90% expense ratio.

Dividends

FAOSX vs. BIGIX - Dividend Comparison

FAOSX's dividend yield for the trailing twelve months is around 8.67%, less than BIGIX's 15.67% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BIGIX William Blair International Growth Fund Class I	15.67%	18.45%	7.49%	3.52%	7.84%	11.41%	1.11%	1.29%	9.05%	1.54%	1.80%	1.18%
FAOSX Fidelity Advisor Overseas Fund Class Z	8.67%	8.67%	1.80%	1.12%	0.85%	2.07%	0.00%	1.70%	5.30%	3.93%	0.00%	0.00%

Frequently Asked Questions

Can I hold both FAOSX and BIGIX in my portfolio?

FAOSX and BIGIX have a correlation of 0.45, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, FAOSX or BIGIX?

BIGIX has higher volatility (7.60%) compared to FAOSX (0.00%). In terms of maximum drawdown, FAOSX dropped -36.24% vs BIGIX's -65.22%.

Which has better risk-adjusted returns?

BIGIX currently has the higher Sharpe Ratio (1.66 vs -0.05), 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.