FSOSX vs. BDOKX

Last updated Jun 4, 2026

FSOSX (Fidelity Series Overseas Fund) and BDOKX (iShares MSCI Total International Index Fund Class K) are both Foreign Large Cap Equities funds. Over the past 5 years, FSOSX returned 6.73%/yr vs 8.79%/yr for BDOKX. Their correlation of 0.91 suggests significant overlap in exposure. FSOSX charges 0.01%/yr vs 0.09%/yr for BDOKX.

Performance

FSOSX vs. BDOKX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Series Overseas Fund (FSOSX) and iShares MSCI Total International Index Fund Class K (BDOKX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, FSOSX achieves a 5.63% return, which is significantly lower than BDOKX's 15.93% return.

FSOSX

• 1D: 0.96%
• 1M: 3.89%
• YTD: 5.63%
• 6M: 7.55%
• 1Y: 8.98%
• 3Y*: 13.16%
• 5Y*: 6.73%
• 10Y*: —

BDOKX

• 1D: 0.74%
• 1M: 6.16%
• YTD: 15.93%
• 6M: 18.68%
• 1Y: 33.80%
• 3Y*: 19.98%
• 5Y*: 8.79%
• 10Y*: 9.87%

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

FSOSX vs. BDOKX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019
FSOSX Fidelity Series Overseas Fund	5.63%	21.29%	5.87%	21.49%	-23.25%	19.59%	16.36%	7.78%
BDOKX iShares MSCI Total International Index Fund Class K	15.93%	32.56%	5.37%	15.26%	-16.40%	7.68%	10.77%	6.77%

Correlation

The correlation between FSOSX and BDOKX is 0.93, 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	0.93
Correlation (3Y) Calculated over the trailing 3-year period	0.91
Correlation (5Y) Calculated over the trailing 5-year period	0.91
Correlation (All Time) Calculated using the full available price history since Jul 1, 2019	0.91

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

Return for Risk

FSOSX vs. BDOKX — Risk / Return Rank

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

FSOSX

FSOSX Risk / Return Rank: 7
FSOSX Sharpe Ratio Rank: 6
FSOSX Sortino Ratio Rank: 6
FSOSX Omega Ratio Rank: 6
FSOSX Calmar Ratio Rank: 7
FSOSX Martin Ratio Rank: 8

BDOKX

BDOKX Risk / Return Rank: 57
BDOKX Sharpe Ratio Rank: 60
BDOKX Sortino Ratio Rank: 54
BDOKX Omega Ratio Rank: 57
BDOKX Calmar Ratio Rank: 59
BDOKX Martin Ratio Rank: 58

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.

FSOSX vs. BDOKX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Series Overseas Fund (FSOSX) and iShares MSCI Total International Index Fund Class K (BDOKX). 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.

	FSOSX	BDOKX	Difference
Sharpe ratio: Return per unit of total volatility	0.50	2.28	-1.78
Sortino ratio: Return per unit of downside risk	0.83	3.10	-2.27
Omega ratio: Gain probability vs. loss probability	1.10	1.42	-0.32
Calmar ratio: Return relative to maximum drawdown	0.68	2.93	-2.26
Martin ratio: Return relative to average drawdown	2.42	11.58	-9.16
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

FSOSX vs. BDOKX - Sharpe Ratio Comparison

The current FSOSX Sharpe Ratio is 0.50, which is lower than the BDOKX Sharpe Ratio of 2.28. The chart below compares the historical Sharpe Ratios of FSOSX and BDOKX, 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

	FSOSX	BDOKX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.50	2.28	-1.78
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.38	0.57	-0.19
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	0.61	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.51	0.39	+0.12

Drawdowns

FSOSX vs. BDOKX - Drawdown Comparison

The maximum FSOSX drawdown since its inception was -35.36%, roughly equal to the maximum BDOKX drawdown of -34.22%. Use the drawdown chart below to compare losses from any high point for FSOSX and BDOKX.

Drawdown Indicators

	FSOSX	BDOKX	Difference
Max Drawdown Largest peak-to-trough decline	-35.36%	-34.22%	-1.14%
Max Drawdown (1Y) Largest decline over 1 year	-12.39%	-11.38%	-1.01%
Max Drawdown (3Y) Largest decline over 3 years	-14.07%	-13.54%	-0.53%
Max Drawdown (5Y) Largest decline over 5 years	-35.36%	-30.23%	-5.13%
Max Drawdown (10Y) Largest decline over 10 years	—	-34.22%	—
Current Drawdown Current decline from peak	-1.31%	0.00%	-1.31%
Average Drawdown Average peak-to-trough decline	-7.78%	-8.23%	+0.45%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.46%	2.88%	+0.58%

Volatility

FSOSX vs. BDOKX - Volatility Comparison

Fidelity Series Overseas Fund (FSOSX) has a higher volatility of 6.14% compared to iShares MSCI Total International Index Fund Class K (BDOKX) at 4.99%. This indicates that FSOSX's price experiences larger fluctuations and is considered to be riskier than BDOKX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FSOSX	BDOKX	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.14%	4.99%	+1.15%
Volatility (6M) Calculated over the trailing 6-month period	14.30%	12.32%	+1.98%
Volatility (1Y) Calculated over the trailing 1-year period	16.80%	14.67%	+2.13%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.67%	15.46%	+2.21%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	19.05%	16.27%	+2.78%

FSOSX vs. BDOKX - Expense Ratio Comparison

FSOSX has a 0.01% expense ratio, which is lower than BDOKX's 0.09% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

FSOSX vs. BDOKX - Dividend Comparison

FSOSX's dividend yield for the trailing twelve months is around 8.66%, more than BDOKX's 2.48% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BDOKX iShares MSCI Total International Index Fund Class K	2.48%	3.01%	2.84%	2.94%	2.84%	3.01%	1.98%	4.48%	3.28%	1.81%	3.51%	3.87%
FSOSX Fidelity Series Overseas Fund	8.66%	9.15%	2.25%	1.63%	1.80%	2.92%	1.12%	0.37%	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both FSOSX and BDOKX in my portfolio?

With a correlation of 0.93, FSOSX and BDOKX 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, FSOSX or BDOKX?

FSOSX has higher volatility (6.14%) compared to BDOKX (4.99%). In terms of maximum drawdown, FSOSX dropped -35.36% vs BDOKX's -34.22%.

Which has better risk-adjusted returns?

BDOKX currently has the higher Sharpe Ratio (2.28 vs 0.50), 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.