MIEKX vs. TRIEX

Last updated Jun 24, 2026

MIEKX (MFS International Equity Fund Class R6) and TRIEX (Nuveen International Equity Index Fund Retirement Class) are both International Equity funds. MIEKX is actively managed, while TRIEX is passively managed. Over the past 3 years, MIEKX returned 11.96%/yr vs 17.31%/yr for TRIEX. Their correlation of 0.94 suggests significant overlap in exposure. MIEKX charges 0.73%/yr vs 0.30%/yr for TRIEX.

Performance

MIEKX vs. TRIEX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in MFS International Equity Fund Class R6 (MIEKX) and Nuveen International Equity Index Fund Retirement Class (TRIEX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, MIEKX achieves a 3.06% return, which is significantly lower than TRIEX's 10.66% return.

MIEKX

• 1D: 0.00%
• 1M: 0.48%
• YTD: 3.06%
• 6M: 2.55%
• 1Y: 11.57%
• 3Y*: 11.96%
• 5Y*: —
• 10Y*: —

TRIEX

• 1D: 0.19%
• 1M: 2.16%
• YTD: 10.66%
• 6M: 10.12%
• 1Y: 24.18%
• 3Y*: 17.31%
• 5Y*: 9.04%
• 10Y*: 9.96%

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

MIEKX vs. TRIEX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023
MIEKX MFS International Equity Fund Class R6	3.06%	23.12%	4.02%	5.55%
TRIEX Nuveen International Equity Index Fund Retirement Class	10.66%	31.24%	3.41%	6.52%

Correlation

The correlation between MIEKX and TRIEX is 0.92, 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	0.92
Correlation (3Y) Calculated over the trailing 3-year period	0.94
Correlation (All Time) Calculated using the full available price history since May 17, 2023	0.94

The correlation between MIEKX and TRIEX has been stable across timeframes, ranging from 0.92 to 0.94 - a consistent structural relationship.

Return for Risk

MIEKX vs. TRIEX — Risk / Return Rank

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

MIEKX

MIEKX Risk / Return Rank: 13
MIEKX Sharpe Ratio Rank: 12
MIEKX Sortino Ratio Rank: 13
MIEKX Omega Ratio Rank: 13
MIEKX Calmar Ratio Rank: 12
MIEKX Martin Ratio Rank: 15

TRIEX

TRIEX Risk / Return Rank: 37
TRIEX Sharpe Ratio Rank: 37
TRIEX Sortino Ratio Rank: 36
TRIEX Omega Ratio Rank: 36
TRIEX Calmar Ratio Rank: 38
TRIEX Martin Ratio Rank: 41

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.

MIEKX vs. TRIEX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for MFS International Equity Fund Class R6 (MIEKX) and Nuveen International Equity Index Fund Retirement Class (TRIEX). 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.

	MIEKX	TRIEX	Difference
Sharpe ratio: Return per unit of total volatility	0.91	1.63	-0.72
Sortino ratio: Return per unit of downside risk	1.35	2.31	-0.96
Omega ratio: Gain probability vs. loss probability	1.17	1.29	-0.13
Calmar ratio: Return relative to maximum drawdown	1.07	2.23	-1.16
Martin ratio: Return relative to average drawdown	3.73	8.28	-4.55

MIEKX vs. TRIEX - Sharpe Ratio Comparison

The current MIEKX Sharpe Ratio is 0.91, which is lower than the TRIEX Sharpe Ratio of 1.63. The chart below compares the historical Sharpe Ratios of MIEKX and TRIEX, 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

MIEKX vs. TRIEX - Drawdown Comparison

The maximum MIEKX drawdown since its inception was -13.42%, smaller than the maximum TRIEX drawdown of -60.73%. Use the drawdown chart below to compare losses from any high point for MIEKX and TRIEX.

Drawdown Indicators

	MIEKX	TRIEX	Difference
Max Drawdown Largest peak-to-trough decline	-13.42%	-60.73%	+47.31%
Max Drawdown (1Y) Largest decline over 1 year	-11.30%	-11.37%	+0.07%
Max Drawdown (3Y) Largest decline over 3 years	-13.42%	-13.55%	+0.13%
Max Drawdown (5Y) Largest decline over 5 years	—	-29.44%	—
Max Drawdown (10Y) Largest decline over 10 years	—	-33.96%	—
Current Drawdown Current decline from peak	-1.67%	0.00%	-1.67%
Average Drawdown Average peak-to-trough decline	-2.82%	-11.42%	+8.60%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.22%	3.05%	+0.17%

Volatility

MIEKX vs. TRIEX - Volatility Comparison

The current volatility for MFS International Equity Fund Class R6 (MIEKX) is 3.59%, while Nuveen International Equity Index Fund Retirement Class (TRIEX) has a volatility of 4.82%. This indicates that MIEKX experiences smaller price fluctuations and is considered to be less risky than TRIEX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MIEKX	TRIEX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.59%	4.82%	-1.23%
Volatility (6M) Calculated over the trailing 6-month period	10.60%	12.94%	-2.34%
Volatility (1Y) Calculated over the trailing 1-year period	13.31%	15.59%	-2.28%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	13.25%	16.19%	-2.94%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	13.25%	16.63%	-3.38%

MIEKX vs. TRIEX - Expense Ratio Comparison

MIEKX has a 0.73% expense ratio, which is higher than TRIEX's 0.30% expense ratio.

Dividends

MIEKX vs. TRIEX - Dividend Comparison

MIEKX's dividend yield for the trailing twelve months is around 2.52%, less than TRIEX's 3.22% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MIEKX MFS International Equity Fund Class R6	2.52%	2.60%	1.41%	1.67%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
TRIEX Nuveen International Equity Index Fund Retirement Class	3.22%	3.57%	2.84%	2.83%	2.49%	2.69%	1.70%	2.78%	3.05%	2.51%	2.65%	2.72%

Frequently Asked Questions

Can I hold both MIEKX and TRIEX in my portfolio?

With a correlation of 0.92, MIEKX and TRIEX 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, MIEKX or TRIEX?

TRIEX has higher volatility (4.82%) compared to MIEKX (3.59%). In terms of maximum drawdown, MIEKX dropped -13.42% vs TRIEX's -60.73%.

Which has better risk-adjusted returns?

TRIEX currently has the higher Sharpe Ratio (1.63 vs 0.91), 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.