BSPGX vs. MGRVX

Last updated Jun 4, 2026

BSPGX (iShares S&P 500 Index Fund Class G) and MGRVX (MFS International Growth Fund Class R4) are both mutual funds - BSPGX is a S&P 500 fund tracking the S&P 500 Index, while MGRVX is a Foreign Large Cap Equities fund managed by MFS. Over the past 5 years, BSPGX returned 14.26%/yr vs 6.41%/yr for MGRVX. A 0.74 correlation means they provide meaningful diversification when combined. BSPGX charges 0.01%/yr vs 0.83%/yr for MGRVX.

Performance

BSPGX vs. MGRVX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares S&P 500 Index Fund Class G (BSPGX) and MFS International Growth Fund Class R4 (MGRVX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, BSPGX achieves a 11.70% return, which is significantly higher than MGRVX's 4.12% return.

BSPGX

• 1D: 0.13%
• 1M: 5.80%
• YTD: 11.70%
• 6M: 11.73%
• 1Y: 28.95%
• 3Y*: 22.73%
• 5Y*: 14.26%
• 10Y*: —

MGRVX

• 1D: 0.45%
• 1M: 3.75%
• YTD: 4.12%
• 6M: 5.08%
• 1Y: 11.71%
• 3Y*: 12.48%
• 5Y*: 6.41%
• 10Y*: 9.95%

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

BSPGX vs. MGRVX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019
BSPGX iShares S&P 500 Index Fund Class G	11.70%	17.85%	24.96%	26.27%	-18.12%	28.66%	19.16%	11.06%
MGRVX MFS International Growth Fund Class R4	4.12%	21.04%	9.10%	14.82%	-15.10%	9.50%	15.70%	6.85%

Correlation

The correlation between BSPGX and MGRVX is 0.69, 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	0.69
Correlation (3Y) Calculated over the trailing 3-year period	0.69
Correlation (5Y) Calculated over the trailing 5-year period	0.72
Correlation (All Time) Calculated using the full available price history since Jul 3, 2019	0.74

The correlation between BSPGX and MGRVX has been stable across timeframes, ranging from 0.69 to 0.74 - a consistent structural relationship.

Return for Risk

BSPGX vs. MGRVX — Risk / Return Rank

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

BSPGX

BSPGX Risk / Return Rank: 73
BSPGX Sharpe Ratio Rank: 76
BSPGX Sortino Ratio Rank: 67
BSPGX Omega Ratio Rank: 67
BSPGX Calmar Ratio Rank: 73
BSPGX Martin Ratio Rank: 83

MGRVX

MGRVX Risk / Return Rank: 10
MGRVX Sharpe Ratio Rank: 10
MGRVX Sortino Ratio Rank: 10
MGRVX Omega Ratio Rank: 10
MGRVX Calmar Ratio Rank: 9
MGRVX Martin Ratio Rank: 10

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.

BSPGX vs. MGRVX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares S&P 500 Index Fund Class G (BSPGX) and MFS International Growth Fund Class R4 (MGRVX). 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.

	BSPGX	MGRVX	Difference
Sharpe ratio: Return per unit of total volatility	2.52	0.84	+1.68
Sortino ratio: Return per unit of downside risk	3.42	1.25	+2.17
Omega ratio: Gain probability vs. loss probability	1.46	1.15	+0.31
Calmar ratio: Return relative to maximum drawdown	3.35	0.89	+2.46
Martin ratio: Return relative to average drawdown	15.67	3.02	+12.65
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

BSPGX vs. MGRVX - Sharpe Ratio Comparison

The current BSPGX Sharpe Ratio is 2.52, which is higher than the MGRVX Sharpe Ratio of 0.84. The chart below compares the historical Sharpe Ratios of BSPGX and MGRVX, 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

	BSPGX	MGRVX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.52	0.84	+1.68
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.85	0.41	+0.44
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	0.63	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.83	0.44	+0.39

Drawdowns

BSPGX vs. MGRVX - Drawdown Comparison

The maximum BSPGX drawdown since its inception was -33.74%, smaller than the maximum MGRVX drawdown of -36.30%. Use the drawdown chart below to compare losses from any high point for BSPGX and MGRVX.

Drawdown Indicators

	BSPGX	MGRVX	Difference
Max Drawdown Largest peak-to-trough decline	-33.74%	-36.30%	+2.56%
Max Drawdown (1Y) Largest decline over 1 year	-8.90%	-12.40%	+3.50%
Max Drawdown (3Y) Largest decline over 3 years	-18.73%	-13.61%	-5.12%
Max Drawdown (5Y) Largest decline over 5 years	-24.50%	-30.56%	+6.06%
Max Drawdown (10Y) Largest decline over 10 years	—	-30.56%	—
Current Drawdown Current decline from peak	0.00%	-2.73%	+2.73%
Average Drawdown Average peak-to-trough decline	-5.09%	-6.65%	+1.56%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.90%	3.67%	-1.77%

Volatility

BSPGX vs. MGRVX - Volatility Comparison

The current volatility for iShares S&P 500 Index Fund Class G (BSPGX) is 2.82%, while MFS International Growth Fund Class R4 (MGRVX) has a volatility of 3.94%. This indicates that BSPGX experiences smaller price fluctuations and is considered to be less risky than MGRVX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	BSPGX	MGRVX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.82%	3.94%	-1.12%
Volatility (6M) Calculated over the trailing 6-month period	8.97%	10.70%	-1.73%
Volatility (1Y) Calculated over the trailing 1-year period	11.85%	13.26%	-1.41%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.88%	15.60%	+1.28%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	20.01%	15.75%	+4.26%

BSPGX vs. MGRVX - Expense Ratio Comparison

BSPGX has a 0.01% expense ratio, which is lower than MGRVX's 0.83% expense ratio.

Dividends

BSPGX vs. MGRVX - Dividend Comparison

BSPGX's dividend yield for the trailing twelve months is around 1.58%, less than MGRVX's 5.28% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BSPGX iShares S&P 500 Index Fund Class G	1.58%	1.74%	1.43%	1.52%	2.04%	1.83%	2.09%	2.25%	0.00%	0.00%	0.00%	0.00%
MGRVX MFS International Growth Fund Class R4	5.28%	5.50%	6.21%	2.73%	2.94%	6.84%	0.72%	1.48%	4.10%	2.53%	1.22%	1.15%

Frequently Asked Questions

Can I hold both BSPGX and MGRVX in my portfolio?

BSPGX and MGRVX have a correlation of 0.69, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, BSPGX or MGRVX?

MGRVX has higher volatility (3.94%) compared to BSPGX (2.82%). In terms of maximum drawdown, BSPGX dropped -33.74% vs MGRVX's -36.30%.

Which has better risk-adjusted returns?

BSPGX currently has the higher Sharpe Ratio (2.52 vs 0.84), 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.