DBLDX vs. FBLTX

Last updated Jun 4, 2026

DBLDX (DoubleLine Long Duration Total Return Bond Fund) and FBLTX (Fidelity SAI Long-Term Treasury Bond Index Fund) are both Government Bonds funds. Over the past 10 years, DBLDX returned -0.81%/yr vs -1.68%/yr for FBLTX. With a 0.97 correlation, they move nearly in lockstep. DBLDX charges 0.50%/yr vs 0.03%/yr for FBLTX.

Performance

DBLDX vs. FBLTX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in DoubleLine Long Duration Total Return Bond Fund (DBLDX) and Fidelity SAI Long-Term Treasury Bond Index Fund (FBLTX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, DBLDX achieves a 0.13% return, which is significantly higher than FBLTX's -0.08% return. Over the past 10 years, DBLDX has outperformed FBLTX with an annualized return of -0.81%, while FBLTX has yielded a comparatively lower -1.68% annualized return.

DBLDX

• 1D: 0.16%
• 1M: 0.92%
• YTD: 0.13%
• 6M: -1.11%
• 1Y: 6.46%
• 3Y*: 0.81%
• 5Y*: -4.73%
• 10Y*: -0.81%

FBLTX

• 1D: 0.15%
• 1M: 1.13%
• YTD: -0.08%
• 6M: -1.63%
• 1Y: 5.28%
• 3Y*: -1.70%
• 5Y*: -6.17%
• 10Y*: -1.68%

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

DBLDX vs. FBLTX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
DBLDX DoubleLine Long Duration Total Return Bond Fund	0.13%	6.25%	-4.42%	3.79%	-29.25%	-3.91%	14.17%	14.19%	-0.79%	6.75%
FBLTX Fidelity SAI Long-Term Treasury Bond Index Fund	-0.08%	4.39%	-8.05%	2.71%	-31.84%	-4.89%	18.27%	14.36%	-1.24%	9.06%

Correlation

The correlation between DBLDX and FBLTX is 0.95 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.95
Correlation (3Y) Calculated over the trailing 3-year period	0.97
Correlation (5Y) Calculated over the trailing 5-year period	0.98
Correlation (10Y) Calculated over the trailing 10-year period	0.97
Correlation (All Time) Calculated using the full available price history since Oct 19, 2015	0.97

The correlation between DBLDX and FBLTX has been stable across timeframes, ranging from 0.95 to 0.98 - a consistent structural relationship.

Return for Risk

DBLDX vs. FBLTX — Risk / Return Rank

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

DBLDX

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

FBLTX

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

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.

DBLDX vs. FBLTX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for DoubleLine Long Duration Total Return Bond Fund (DBLDX) and Fidelity SAI Long-Term Treasury Bond Index Fund (FBLTX). 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.

	DBLDX	FBLTX	Difference
Sharpe ratio: Return per unit of total volatility	0.74	0.53	+0.21
Sortino ratio: Return per unit of downside risk	1.14	0.82	+0.32
Omega ratio: Gain probability vs. loss probability	1.13	1.09	+0.04
Calmar ratio: Return relative to maximum drawdown	0.86	0.67	+0.19
Martin ratio: Return relative to average drawdown	2.45	1.71	+0.74
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

DBLDX vs. FBLTX - Sharpe Ratio Comparison

The current DBLDX Sharpe Ratio is 0.74, which is higher than the FBLTX Sharpe Ratio of 0.53. The chart below compares the historical Sharpe Ratios of DBLDX and FBLTX, 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

	DBLDX	FBLTX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.74	0.53	+0.21
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.36	-0.39	+0.04
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	-0.07	-0.12	+0.05
Sharpe Ratio (All Time) Calculated using the full available price history	0.01	-0.05	+0.06

Drawdowns

DBLDX vs. FBLTX - Drawdown Comparison

The maximum DBLDX drawdown since its inception was -45.96%, smaller than the maximum FBLTX drawdown of -49.06%. Use the drawdown chart below to compare losses from any high point for DBLDX and FBLTX.

Drawdown Indicators

	DBLDX	FBLTX	Difference
Max Drawdown Largest peak-to-trough decline	-45.96%	-49.06%	+3.10%
Max Drawdown (1Y) Largest decline over 1 year	-7.54%	-7.66%	+0.12%
Max Drawdown (3Y) Largest decline over 3 years	-16.52%	-19.12%	+2.60%
Max Drawdown (5Y) Largest decline over 5 years	-40.48%	-44.19%	+3.71%
Max Drawdown (10Y) Largest decline over 10 years	-45.96%	-49.06%	+3.10%
Current Drawdown Current decline from peak	-34.44%	-41.01%	+6.57%
Average Drawdown Average peak-to-trough decline	-17.55%	-20.99%	+3.44%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.64%	3.01%	-0.37%

Volatility

DBLDX vs. FBLTX - Volatility Comparison

DoubleLine Long Duration Total Return Bond Fund (DBLDX) and Fidelity SAI Long-Term Treasury Bond Index Fund (FBLTX) have volatilities of 2.81% and 2.80%, 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

	DBLDX	FBLTX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.81%	2.80%	+0.01%
Volatility (6M) Calculated over the trailing 6-month period	6.13%	6.56%	-0.43%
Volatility (1Y) Calculated over the trailing 1-year period	8.76%	9.82%	-1.06%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	13.38%	15.70%	-2.32%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	12.27%	14.59%	-2.32%

DBLDX vs. FBLTX - Expense Ratio Comparison

DBLDX has a 0.50% expense ratio, which is higher than FBLTX's 0.03% expense ratio.

Dividends

DBLDX vs. FBLTX - Dividend Comparison

DBLDX's dividend yield for the trailing twelve months is around 5.40%, more than FBLTX's 4.17% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
DBLDX DoubleLine Long Duration Total Return Bond Fund	5.40%	5.14%	4.94%	3.35%	3.48%	2.93%	9.77%	7.60%	3.14%	3.36%	3.15%	3.23%
FBLTX Fidelity SAI Long-Term Treasury Bond Index Fund	4.17%	4.04%	3.60%	3.29%	2.25%	1.81%	6.73%	2.39%	2.87%	2.68%	3.70%	0.39%

Frequently Asked Questions

Can I hold both DBLDX and FBLTX in my portfolio?

With a correlation of 0.95, DBLDX and FBLTX 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, DBLDX or FBLTX?

DBLDX has higher volatility (2.81%) compared to FBLTX (2.80%). In terms of maximum drawdown, DBLDX dropped -45.96% vs FBLTX's -49.06%.

Which has better risk-adjusted returns?

DBLDX currently has the higher Sharpe Ratio (0.74 vs 0.53), 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.