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AGZ vs. SPTL
Performance
Return for Risk
Drawdowns
Volatility
Dividends

AGZ vs. SPTL

Last updated Jun 4, 2026

AGZ (iShares Agency Bond ETF) and SPTL (SPDR Portfolio Long Term Treasury ETF) are both Government Bonds funds - AGZ tracks the Bloomberg U.S. Agency Bond Index (USD) while SPTL tracks the Bloomberg Long U.S. Treasury Index. Both are passively managed. Over the past 10 years, AGZ returned 1.83%/yr vs -1.12%/yr for SPTL. A 0.69 correlation means they provide meaningful diversification when combined. AGZ charges 0.20%/yr vs 0.03%/yr for SPTL.

Performance

AGZ vs. SPTL - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares Agency Bond ETF (AGZ) and SPDR Portfolio Long Term Treasury ETF (SPTL). The values are adjusted to include any dividend payments, if applicable.

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Returns By Period

In the year-to-date period, AGZ achieves a 0.16% return, which is significantly higher than SPTL's -0.38% return. Over the past 10 years, AGZ has outperformed SPTL with an annualized return of 1.83%, while SPTL has yielded a comparatively lower -1.12% annualized return.

AGZ

1D
-0.13%
1M
-0.03%
YTD
0.16%
6M
0.29%
1Y
3.95%
3Y*
4.10%
5Y*
1.15%
10Y*
1.83%

SPTL

1D
-0.38%
1M
0.71%
YTD
-0.38%
6M
-1.67%
1Y
5.22%
3Y*
-0.70%
5Y*
-5.32%
10Y*
-1.12%
*Multi-year figures are annualized to reflect compound growth (CAGR)

AGZ vs. SPTL - Yearly Performance Comparison

2026 (YTD)202520242023202220212020201920182017
AGZ
iShares Agency Bond ETF		0.16%6.05%3.08%5.18%-7.77%-1.05%5.77%5.51%1.32%2.01%
SPTL
SPDR Portfolio Long Term Treasury ETF		-0.38%5.28%-6.23%3.30%-29.44%-4.99%18.07%13.74%-1.57%9.01%

Correlation

The correlation between AGZ and SPTL is 0.73, 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

0.73

Correlation (3Y)
Calculated over the trailing 3-year period

0.77

Correlation (5Y)
Calculated over the trailing 5-year period

0.78

Correlation (10Y)
Calculated over the trailing 10-year period

0.76

Correlation (All Time)
Calculated using the full available price history since Nov 10, 2008

0.69

The correlation between AGZ and SPTL has been stable across timeframes, ranging from 0.69 to 0.78 - a consistent structural relationship.

Compare stocks, funds, or ETFs

Search for stocks, ETFs, and funds for a quick comparison or use the comparison tool for more options.

iShares Agency Bond ETF

SPDR Portfolio Long Term Treasury ETF

Often compared with AGZ:
AGZ vs. AGZDAGZ vs. FGOVXAGZ vs. NYFAGZ vs. GVIAGZ vs. LLDYXAGZ vs. GBFAGZ vs. USFR
Often compared with SPTL:
SPTL vs. TLTSPTL vs. VGLTSPTL vs. EDVSPTL vs. SCHQSPTL vs. TLHSPTL vs. BNDSPTL vs. VUSTX

Return for Risk

AGZ vs. SPTL — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.
AGZ
AGZ Risk / Return Rank: 5050
Overall Rank
AGZ Sharpe Ratio Rank: 4343
Sharpe Ratio Rank
AGZ Sortino Ratio Rank: 4747
Sortino Ratio Rank
AGZ Omega Ratio Rank: 4444
Omega Ratio Rank
AGZ Calmar Ratio Rank: 5959
Calmar Ratio Rank
AGZ Martin Ratio Rank: 5656
Martin Ratio Rank
SPTL
SPTL Risk / Return Rank: 1717
Overall Rank
SPTL Sharpe Ratio Rank: 1818
Sharpe Ratio Rank
SPTL Sortino Ratio Rank: 1717
Sortino Ratio Rank
SPTL Omega Ratio Rank: 1616
Omega Ratio Rank
SPTL Calmar Ratio Rank: 1818
Calmar Ratio Rank
SPTL Martin Ratio Rank: 1818
Martin Ratio Rank
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.

AGZ vs. SPTL - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares Agency Bond ETF (AGZ) and SPDR Portfolio Long Term Treasury ETF (SPTL). 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.

AGZSPTLDifference
Sharpe ratioReturn per unit of total volatility
1.54
0.59

+0.95

Sortino ratioReturn per unit of downside risk
2.33
0.90

+1.43

Omega ratioGain probability vs. loss probability

1.28

1.10

+0.18

Calmar ratioReturn relative to maximum drawdown

2.93

0.74

+2.19

Martin ratioReturn relative to average drawdown

9.76

1.94

+7.82

Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

AGZ vs. SPTL - Sharpe Ratio Comparison

The current AGZ Sharpe Ratio is 1.54, which is higher than the SPTL Sharpe Ratio of 0.59. The chart below compares the historical Sharpe Ratios of AGZ and SPTL, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

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Sharpe Ratios by Period

AGZSPTLDifference

Sharpe Ratio (1Y)

Calculated over the trailing 1-year period

1.54

0.59

+0.95

Sharpe Ratio (5Y)

Calculated over the trailing 5-year period

0.33

-0.37

+0.69

Sharpe Ratio (10Y)

Calculated over the trailing 10-year period

0.60

-0.08

+0.68

Sharpe Ratio (All Time)

Calculated using the full available price history

0.68

0.24

+0.44

Drawdowns

AGZ vs. SPTL - Drawdown Comparison

The maximum AGZ drawdown since its inception was -11.01%, smaller than the maximum SPTL drawdown of -46.20%. Use the drawdown chart below to compare losses from any high point for AGZ and SPTL.

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Drawdown Indicators

AGZSPTLDifference

Max Drawdown

Largest peak-to-trough decline

-11.01%

-46.20%

+35.19%

Max Drawdown (1Y)

Largest decline over 1 year

-1.35%

-7.04%

+5.69%

Max Drawdown (3Y)

Largest decline over 3 years

-1.85%

-17.55%

+15.70%

Max Drawdown (5Y)

Largest decline over 5 years

-10.66%

-41.02%

+30.36%

Max Drawdown (10Y)

Largest decline over 10 years

-11.01%

-46.20%

+35.19%

Current Drawdown

Current decline from peak

-0.78%

-36.87%

+36.09%

Average Drawdown

Average peak-to-trough decline

-1.61%

-14.24%

+12.63%

Ulcer Index

Depth and duration of drawdowns from previous peaks

0.41%

2.69%

-2.28%

Volatility

AGZ vs. SPTL - Volatility Comparison

The current volatility for iShares Agency Bond ETF (AGZ) is 0.76%, while SPDR Portfolio Long Term Treasury ETF (SPTL) has a volatility of 2.63%. This indicates that AGZ experiences smaller price fluctuations and is considered to be less risky than SPTL based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

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Volatility by Period

AGZSPTLDifference

Volatility (1M)

Calculated over the trailing 1-month period

0.76%

2.63%

-1.87%

Volatility (6M)

Calculated over the trailing 6-month period

1.93%

5.97%

-4.04%

Volatility (1Y)

Calculated over the trailing 1-year period

2.58%

8.92%

-6.34%

Volatility (5Y)

Calculated over the trailing 5-year period, annualized

3.54%

14.63%

-11.09%

Volatility (10Y)

Calculated over the trailing 10-year period, annualized

3.03%

13.95%

-10.92%

AGZ vs. SPTL - Expense Ratio Comparison

AGZ has a 0.20% expense ratio, which is higher than SPTL's 0.03% expense ratio. However, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

AGZ vs. SPTL - Dividend Comparison

AGZ's dividend yield for the trailing twelve months is around 3.73%, less than SPTL's 4.21% yield.

PositionTTM20252024202320222021202020192018201720162015
AGZ
iShares Agency Bond ETF		3.73%3.75%3.48%3.14%1.56%0.96%2.25%2.32%2.15%1.58%1.52%1.30%
SPTL
SPDR Portfolio Long Term Treasury ETF		4.21%4.12%4.03%3.24%2.75%1.68%1.71%2.45%2.69%2.53%2.56%2.60%

Frequently Asked Questions

AGZ and SPTL have a correlation of 0.73, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

SPTL has higher volatility (2.63%) compared to AGZ (0.76%). In terms of maximum drawdown, AGZ dropped -11.01% vs SPTL's -46.20%.

On 10-year performance, AGZ leads with 1.83% vs -1.12% for SPTL. On fees, SPTL is cheaper at 0.03% per year. On volatility, AGZ has been the lower-risk option at 0.76%. The better choice depends on whether you care most about return, fees, risk, or income.

Over the 10-year period, AGZ has performed better with a 1.83% return vs -1.12%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

SPTL is cheaper with a 0.03% expense ratio, compared with 0.20% for AGZ.

SPTL has the higher dividend yield at 4.21%, compared with 3.73% for AGZ.

AGZ tracks Bloomberg U.S. Agency Bond Index (USD), while SPTL tracks Bloomberg Long U.S. Treasury Index. They also come from different issuers: iShares and State Street. Their fees differ too: 0.20% for AGZ and 0.03% for SPTL.

AGZ currently has the higher Sharpe Ratio (1.54 vs 0.59), 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.

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