SPMB vs. IGOV

Last updated Apr 1, 2026

Compare and contrast key facts about SPDR Portfolio Mortgage Backed Bond ETF (SPMB) and iShares International Treasury Bond ETF (IGOV).

SPMB and IGOV are both exchange-traded funds (ETFs), meaning they are traded on stock exchanges and can be bought and sold throughout the day. SPMB is a passively managed fund by State Street that tracks the performance of the Bloomberg US Aggregate Securitized - MBS. It was launched on Jan 15, 2009. IGOV is a passively managed fund by iShares that tracks the performance of the S&P/Citigroup International Treasury Bond Index Ex-US. It was launched on Jan 21, 2009. Both SPMB and IGOV are passive ETFs, meaning that they are not actively managed but aim to replicate the performance of the underlying index as closely as possible.

Performance

SPMB vs. IGOV - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in SPDR Portfolio Mortgage Backed Bond ETF (SPMB) and iShares International Treasury Bond ETF (IGOV). The values are adjusted to include any dividend payments, if applicable.

SPMB vs. IGOV - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
SPMB SPDR Portfolio Mortgage Backed Bond ETF	0.51%	8.29%	1.35%	5.09%	-12.05%	-1.46%	4.19%	6.16%	1.01%	2.13%
IGOV iShares International Treasury Bond ETF	-1.44%	9.96%	-6.50%	5.57%	-22.07%	-9.25%	10.88%	3.76%	-2.60%	11.38%

Returns By Period

In the year-to-date period, SPMB achieves a 0.51% return, which is significantly higher than IGOV's -1.44% return. Over the past 10 years, SPMB has outperformed IGOV with an annualized return of 1.29%, while IGOV has yielded a comparatively lower -1.34% annualized return.

SPMB

• 1D: 0.31%
• 1M: -1.58%
• YTD: 0.51%
• 6M: 1.98%
• 1Y: 5.73%
• 3Y*: 4.11%
• 5Y*: 0.37%
• 10Y*: 1.29%

IGOV

• 1D: 1.23%
• 1M: -4.49%
• YTD: -1.44%
• 6M: -2.25%
• 1Y: 5.63%
• 3Y*: 1.37%
• 5Y*: -4.22%
• 10Y*: -1.34%

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

SPMB vs. IGOV - Expense Ratio Comparison

SPMB has a 0.04% expense ratio, which is lower than IGOV's 0.35% expense ratio.

IGOV

iShares International Treasury Bond ETF

SPMB

SPDR Portfolio Mortgage Backed Bond ETF

Return for Risk

SPMB vs. IGOV — Risk / Return Rank

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

SPMB

SPMB Risk / Return Rank: 66
SPMB Sharpe Ratio Rank: 68
SPMB Sortino Ratio Rank: 68
SPMB Omega Ratio Rank: 59
SPMB Calmar Ratio Rank: 77
SPMB Martin Ratio Rank: 60

IGOV

IGOV Risk / Return Rank: 35
IGOV Sharpe Ratio Rank: 36
IGOV Sortino Ratio Rank: 36
IGOV Omega Ratio Rank: 31
IGOV Calmar Ratio Rank: 40
IGOV Martin Ratio Rank: 31

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.

SPMB vs. IGOV - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for SPDR Portfolio Mortgage Backed Bond ETF (SPMB) and iShares International Treasury Bond ETF (IGOV). 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.

	SPMB	IGOV	Difference
Sharpe ratio Return per unit of total volatility	1.18	0.63	+0.55
Sortino ratio Return per unit of downside risk	1.69	0.98	+0.71
Omega ratio Gain probability vs. loss probability	1.21	1.12	+0.10
Calmar ratio Return relative to maximum drawdown	2.01	0.96	+1.05
Martin ratio Return relative to average drawdown	5.76	2.56	+3.20
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

SPMB vs. IGOV - Sharpe Ratio Comparison

The current SPMB Sharpe Ratio is 1.18, which is higher than the IGOV Sharpe Ratio of 0.63. The chart below compares the historical Sharpe Ratios of SPMB and IGOV, offering insights into how both investments have performed under varying market conditions. These values are calculated using daily returns over the previous 12 months.

Sharpe Ratios by Period

	SPMB	IGOV	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.18	0.63	+0.55
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.05	-0.43	+0.48
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.17	-0.16	+0.33
Sharpe Ratio (All Time) Calculated using the full available price history	0.34	0.01	+0.33

Correlation

The correlation between SPMB and IGOV is 0.36, which is considered to be low. This implies their price changes are not closely related. A low correlation is generally favorable for portfolio diversification, as it helps to reduce overall risk by spreading it across multiple assets with different performance patterns.

Dividends

SPMB vs. IGOV - Dividend Comparison

SPMB's dividend yield for the trailing twelve months is around 4.02%, more than IGOV's 1.43% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
SPMB SPDR Portfolio Mortgage Backed Bond ETF	4.02%	3.98%	3.76%	3.21%	2.98%	2.59%	2.95%	3.24%	3.36%	3.13%	2.99%	3.05%
IGOV iShares International Treasury Bond ETF	1.43%	1.41%	0.59%	0.00%	0.11%	0.39%	0.00%	0.24%	0.31%	0.19%	0.69%	0.12%

Drawdowns

SPMB vs. IGOV - Drawdown Comparison

The maximum SPMB drawdown since its inception was -18.03%, smaller than the maximum IGOV drawdown of -35.88%. Use the drawdown chart below to compare losses from any high point for SPMB and IGOV.

Drawdown Indicators

	SPMB	IGOV	Difference
Max Drawdown Largest peak-to-trough decline	-18.03%	-35.88%	+17.85%
Max Drawdown (1Y) Largest decline over 1 year	-2.93%	-5.70%	+2.77%
Max Drawdown (5Y) Largest decline over 5 years	-17.49%	-33.17%	+15.68%
Max Drawdown (10Y) Largest decline over 10 years	-18.03%	-35.88%	+17.85%
Current Drawdown Current decline from peak	-1.58%	-24.72%	+23.14%
Average Drawdown Average peak-to-trough decline	-2.87%	-10.89%	+8.02%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.02%	2.13%	-1.11%

Volatility

SPMB vs. IGOV - Volatility Comparison

The current volatility for SPDR Portfolio Mortgage Backed Bond ETF (SPMB) is 1.83%, while iShares International Treasury Bond ETF (IGOV) has a volatility of 3.63%. This indicates that SPMB experiences smaller price fluctuations and is considered to be less risky than IGOV based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	SPMB	IGOV	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.83%	3.63%	-1.80%
Volatility (6M) Calculated over the trailing 6-month period	2.77%	5.29%	-2.52%
Volatility (1Y) Calculated over the trailing 1-year period	4.88%	9.04%	-4.16%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	6.73%	9.88%	-3.15%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	7.59%	8.58%	-0.99%