TGLMX vs. MRBIX

Last updated Jun 4, 2026

TGLMX (TCW Total Return Bond Fund) and MRBIX (MFS Total Return Bond Fund) are both Intermediate Core-Plus Bond funds. Over the past 10 years, TGLMX returned 1.53%/yr vs 1.97%/yr for MRBIX. A 0.79 correlation means they provide meaningful diversification when combined. TGLMX charges 0.49%/yr vs 0.45%/yr for MRBIX.

Performance

TGLMX vs. MRBIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in TCW Total Return Bond Fund (TGLMX) and MFS Total Return Bond Fund (MRBIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, TGLMX achieves a 1.25% return, which is significantly higher than MRBIX's 0.52% return. Over the past 10 years, TGLMX has underperformed MRBIX with an annualized return of 1.53%, while MRBIX has yielded a comparatively higher 1.97% annualized return.

TGLMX

• 1D: 0.00%
• 1M: 0.39%
• YTD: 1.25%
• 6M: 1.15%
• 1Y: 7.29%
• 3Y*: 4.76%
• 5Y*: -0.09%
• 10Y*: 1.53%

MRBIX

• 1D: 0.00%
• 1M: 0.55%
• YTD: 0.52%
• 6M: 0.48%
• 1Y: 5.67%
• 3Y*: 4.35%
• 5Y*: 0.23%
• 10Y*: 1.97%

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

TGLMX vs. MRBIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
TGLMX TCW Total Return Bond Fund	1.25%	8.99%	1.82%	5.05%	-16.59%	-1.05%	8.32%	7.28%	0.80%	3.44%
MRBIX MFS Total Return Bond Fund	0.52%	7.35%	1.77%	6.45%	-14.52%	-0.84%	8.83%	9.96%	-1.03%	4.15%

Correlation

The correlation between TGLMX and MRBIX is 0.90, 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	0.90
Correlation (3Y) Calculated over the trailing 3-year period	0.92
Correlation (5Y) Calculated over the trailing 5-year period	0.93
Correlation (10Y) Calculated over the trailing 10-year period	0.89
Correlation (All Time) Calculated using the full available price history since Jan 4, 1999	0.79

The correlation between TGLMX and MRBIX shifts across timeframes, from 0.79 (all time) to 0.93 (5 years), reflecting how their relationship changes across market environments.

Return for Risk

TGLMX vs. MRBIX — Risk / Return Rank

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

TGLMX

TGLMX Risk / Return Rank: 38
TGLMX Sharpe Ratio Rank: 33
TGLMX Sortino Ratio Rank: 36
TGLMX Omega Ratio Rank: 35
TGLMX Calmar Ratio Rank: 51
TGLMX Martin Ratio Rank: 38

MRBIX

MRBIX Risk / Return Rank: 27
MRBIX Sharpe Ratio Rank: 27
MRBIX Sortino Ratio Rank: 29
MRBIX Omega Ratio Rank: 26
MRBIX Calmar Ratio Rank: 30
MRBIX Martin Ratio Rank: 25

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.

TGLMX vs. MRBIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for TCW Total Return Bond Fund (TGLMX) and MFS Total Return Bond Fund (MRBIX). 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.

	TGLMX	MRBIX	Difference
Sharpe ratio Return per unit of total volatility	1.64	1.48	+0.16
Sortino ratio Return per unit of downside risk	2.48	2.24	+0.24
Omega ratio Gain probability vs. loss probability	1.31	1.27	+0.04
Calmar ratio Return relative to maximum drawdown	2.74	2.06	+0.68
Martin ratio Return relative to average drawdown	8.29	6.03	+2.26
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

TGLMX vs. MRBIX - Sharpe Ratio Comparison

The current TGLMX Sharpe Ratio is 1.64, which is comparable to the MRBIX Sharpe Ratio of 1.48. The chart below compares the historical Sharpe Ratios of TGLMX and MRBIX, 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

	TGLMX	MRBIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.64	1.48	+0.16
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.01	0.04	-0.05
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.28	0.40	-0.13
Sharpe Ratio (All Time) Calculated using the full available price history	0.40	0.97	-0.57

Drawdowns

TGLMX vs. MRBIX - Drawdown Comparison

The maximum TGLMX drawdown since its inception was -22.26%, which is greater than MRBIX's maximum drawdown of -19.25%. Use the drawdown chart below to compare losses from any high point for TGLMX and MRBIX.

Drawdown Indicators

	TGLMX	MRBIX	Difference
Max Drawdown Largest peak-to-trough decline	-22.26%	-19.25%	-3.01%
Max Drawdown (1Y) Largest decline over 1 year	-2.63%	-2.77%	+0.14%
Max Drawdown (3Y) Largest decline over 3 years	-8.56%	-6.29%	-2.27%
Max Drawdown (5Y) Largest decline over 5 years	-22.17%	-19.25%	-2.92%
Max Drawdown (10Y) Largest decline over 10 years	-22.26%	-19.25%	-3.01%
Current Drawdown Current decline from peak	-2.72%	-1.29%	-1.43%
Average Drawdown Average peak-to-trough decline	-3.80%	-2.47%	-1.33%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.86%	0.94%	-0.08%

Volatility

TGLMX vs. MRBIX - Volatility Comparison

TCW Total Return Bond Fund (TGLMX) has a higher volatility of 1.44% compared to MFS Total Return Bond Fund (MRBIX) at 1.35%. This indicates that TGLMX's price experiences larger fluctuations and is considered to be riskier than MRBIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	TGLMX	MRBIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.44%	1.35%	+0.09%
Volatility (6M) Calculated over the trailing 6-month period	3.00%	2.73%	+0.27%
Volatility (1Y) Calculated over the trailing 1-year period	4.39%	3.86%	+0.53%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	7.05%	5.73%	+1.32%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	5.59%	4.92%	+0.67%

TGLMX vs. MRBIX - Expense Ratio Comparison

TGLMX has a 0.49% expense ratio, which is higher than MRBIX's 0.45% expense ratio.

Dividends

TGLMX vs. MRBIX - Dividend Comparison

TGLMX's dividend yield for the trailing twelve months is around 6.74%, more than MRBIX's 4.17% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MRBIX MFS Total Return Bond Fund	4.17%	4.21%	3.69%	3.42%	2.39%	3.42%	3.00%	3.06%	2.87%	2.65%	3.02%	3.76%
TGLMX TCW Total Return Bond Fund	6.74%	7.19%	6.52%	6.13%	3.27%	2.08%	3.37%	4.07%	3.55%	2.89%	4.13%	2.88%

Frequently Asked Questions

Can I hold both TGLMX and MRBIX in my portfolio?

With a correlation of 0.90, TGLMX and MRBIX 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, TGLMX or MRBIX?

TGLMX has higher volatility (1.44%) compared to MRBIX (1.35%). In terms of maximum drawdown, TGLMX dropped -22.26% vs MRBIX's -19.25%.

Which has better risk-adjusted returns?

TGLMX currently has the higher Sharpe Ratio (1.64 vs 1.48), 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.