MGBLX vs. FBIIX

Last updated Jun 6, 2026

MGBLX (MFS Global Opportunistic Bond Fund Class R2) and FBIIX (Fidelity International Bond Index Fund) are both Global Bonds funds. Over the past 5 years, MGBLX returned 0.39%/yr vs 0.72%/yr for FBIIX. A 0.73 correlation means they provide meaningful diversification when combined. MGBLX charges 1.19%/yr vs 0.06%/yr for FBIIX.

Performance

MGBLX vs. FBIIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in MFS Global Opportunistic Bond Fund Class R2 (MGBLX) and Fidelity International Bond Index Fund (FBIIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, MGBLX achieves a 0.31% return, which is significantly lower than FBIIX's 0.61% return.

MGBLX

• 1D: 0.12%
• 1M: 0.04%
• YTD: 0.31%
• 6M: 0.60%
• 1Y: 3.91%
• 3Y*: 4.18%
• 5Y*: 0.39%
• 10Y*: 1.57%

FBIIX

• 1D: 0.00%
• 1M: 0.22%
• YTD: 0.61%
• 6M: 0.71%
• 1Y: 2.10%
• 3Y*: 4.12%
• 5Y*: 0.72%
• 10Y*: —

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

MGBLX vs. FBIIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019
MGBLX MFS Global Opportunistic Bond Fund Class R2	0.31%	5.38%	1.81%	7.69%	-11.57%	-3.48%	10.52%	0.24%
FBIIX Fidelity International Bond Index Fund	0.61%	2.66%	4.64%	7.48%	-10.84%	-1.84%	4.43%	-1.13%

Correlation

The correlation between MGBLX and FBIIX is 0.73, 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	0.73
Correlation (3Y) Calculated over the trailing 3-year period	0.81
Correlation (5Y) Calculated over the trailing 5-year period	0.79
Correlation (All Time) Calculated using the full available price history since Oct 11, 2019	0.73

The correlation between MGBLX and FBIIX has been stable across timeframes, ranging from 0.73 to 0.81 - a consistent structural relationship.

Return for Risk

MGBLX vs. FBIIX — Risk / Return Rank

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

MGBLX

MGBLX Risk / Return Rank: 16
MGBLX Sharpe Ratio Rank: 17
MGBLX Sortino Ratio Rank: 19
MGBLX Omega Ratio Rank: 17
MGBLX Calmar Ratio Rank: 14
MGBLX Martin Ratio Rank: 13

FBIIX

FBIIX Risk / Return Rank: 9
FBIIX Sharpe Ratio Rank: 9
FBIIX Sortino Ratio Rank: 9
FBIIX Omega Ratio Rank: 9
FBIIX Calmar Ratio Rank: 9
FBIIX Martin Ratio Rank: 8

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.

MGBLX vs. FBIIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for MFS Global Opportunistic Bond Fund Class R2 (MGBLX) and Fidelity International Bond Index Fund (FBIIX). 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.

	MGBLX	FBIIX	Difference
Sharpe ratio: Return per unit of total volatility	1.12	0.70	+0.41
Sortino ratio: Return per unit of downside risk	1.71	1.02	+0.69
Omega ratio: Gain probability vs. loss probability	1.20	1.13	+0.07
Calmar ratio: Return relative to maximum drawdown	1.17	0.76	+0.41
Martin ratio: Return relative to average drawdown	3.53	2.11	+1.42
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

MGBLX vs. FBIIX - Sharpe Ratio Comparison

The current MGBLX Sharpe Ratio is 1.12, which is higher than the FBIIX Sharpe Ratio of 0.70. The chart below compares the historical Sharpe Ratios of MGBLX and FBIIX, 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

	MGBLX	FBIIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.12	0.70	+0.41
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.09	0.20	-0.11
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.34	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.30	0.22	+0.08

Drawdowns

MGBLX vs. FBIIX - Drawdown Comparison

The maximum MGBLX drawdown since its inception was -18.71%, which is greater than FBIIX's maximum drawdown of -13.79%. Use the drawdown chart below to compare losses from any high point for MGBLX and FBIIX.

Drawdown Indicators

	MGBLX	FBIIX	Difference
Max Drawdown Largest peak-to-trough decline	-18.71%	-13.79%	-4.92%
Max Drawdown (1Y) Largest decline over 1 year	-3.25%	-2.78%	-0.47%
Max Drawdown (3Y) Largest decline over 3 years	-5.74%	-2.78%	-2.96%
Max Drawdown (5Y) Largest decline over 5 years	-17.10%	-13.74%	-3.36%
Max Drawdown (10Y) Largest decline over 10 years	-18.71%	—	—
Current Drawdown Current decline from peak	-1.45%	-1.33%	-0.12%
Average Drawdown Average peak-to-trough decline	-6.55%	-4.12%	-2.43%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.07%	1.00%	+0.07%

Volatility

MGBLX vs. FBIIX - Volatility Comparison

MFS Global Opportunistic Bond Fund Class R2 (MGBLX) and Fidelity International Bond Index Fund (FBIIX) have volatilities of 1.34% and 1.33%, respectively, indicating that both stocks experience similar levels of price fluctuations. This suggests that the risk associated with both stocks, as measured by volatility, is nearly the same. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MGBLX	FBIIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.34%	1.33%	+0.01%
Volatility (6M) Calculated over the trailing 6-month period	2.78%	2.64%	+0.14%
Volatility (1Y) Calculated over the trailing 1-year period	3.42%	3.00%	+0.42%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	4.29%	3.59%	+0.70%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	4.65%	3.42%	+1.23%

MGBLX vs. FBIIX - Expense Ratio Comparison

MGBLX has a 1.19% expense ratio, which is higher than FBIIX's 0.06% expense ratio.

Dividends

MGBLX vs. FBIIX - Dividend Comparison

MGBLX's dividend yield for the trailing twelve months is around 4.25%, more than FBIIX's 4.19% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FBIIX Fidelity International Bond Index Fund	4.19%	4.09%	3.44%	2.85%	1.02%	0.62%	0.74%	0.17%	0.00%	0.00%	0.00%	0.00%
MGBLX MFS Global Opportunistic Bond Fund Class R2	4.25%	4.01%	2.53%	1.55%	2.99%	4.72%	3.15%	1.81%	1.66%	1.08%	1.15%	1.63%

Frequently Asked Questions

Can I hold both MGBLX and FBIIX in my portfolio?

MGBLX and FBIIX have a correlation of 0.73, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, MGBLX or FBIIX?

MGBLX has higher volatility (1.34%) compared to FBIIX (1.33%). In terms of maximum drawdown, MGBLX dropped -18.71% vs FBIIX's -13.79%.

Which has better risk-adjusted returns?

MGBLX currently has the higher Sharpe Ratio (1.12 vs 0.70), 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.