IBGC vs. SPTB

Last updated Jun 6, 2026

IBGC (iShares iBonds Dec 2046 Term Treasury ETF) and SPTB (State Street SPDR Portfolio Treasury ETF) are both Government Bonds funds - IBGC tracks the ICE 2046 Maturity US Treasury Index while SPTB tracks the Bloomberg U.S. Treasury Index. Both are passively managed. Their correlation of 0.93 suggests significant overlap in exposure. IBGC charges 0.07%/yr vs 0.03%/yr for SPTB.

Performance

IBGC vs. SPTB - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares iBonds Dec 2046 Term Treasury ETF (IBGC) and State Street SPDR Portfolio Treasury ETF (SPTB). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

IBGC

• 1D: -0.63%
• 1M: -1.05%
• YTD: —
• 6M: —
• 1Y: —
• 3Y*: —
• 5Y*: —
• 10Y*: —

SPTB

• 1D: -0.32%
• 1M: -0.65%
• YTD: -0.28%
• 6M: -0.14%
• 1Y: 3.19%
• 3Y*: —
• 5Y*: —
• 10Y*: —

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

IBGC vs. SPTB - Yearly Performance Comparison

	2026 (YTD)
IBGC iShares iBonds Dec 2046 Term Treasury ETF	0.21%
SPTB State Street SPDR Portfolio Treasury ETF	0.20%

Correlation

The correlation between IBGC and SPTB is 0.93, indicating a strong positive relationship between their price movements. Combining them offers limited diversification - they tend to fall together during downturns.

	Correlation
Correlation (All Time) Calculated using the full available price history since Mar 27, 2026	0.93

Return for Risk

IBGC vs. SPTB — Risk / Return Rank

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

SPTB

SPTB Risk / Return Rank: 25
SPTB Sharpe Ratio Rank: 27
SPTB Sortino Ratio Rank: 26
SPTB Omega Ratio Rank: 24
SPTB Calmar Ratio Rank: 25
SPTB 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.

IBGC vs. SPTB - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares iBonds Dec 2046 Term Treasury ETF (IBGC) and State Street SPDR Portfolio Treasury ETF (SPTB). 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.

Risk / return metrics aren't available yet — we need at least 12 months of trading data to calculate them.

Sharpe Ratios by Period

	IBGC	SPTB	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	—	0.89	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.13	0.89	-0.76

Drawdowns

IBGC vs. SPTB - Drawdown Comparison

The maximum IBGC drawdown since its inception was -4.29%, smaller than the maximum SPTB drawdown of -4.96%. Use the drawdown chart below to compare losses from any high point for IBGC and SPTB.

Drawdown Indicators

	IBGC	SPTB	Difference
Max Drawdown Largest peak-to-trough decline	-4.29%	-4.96%	+0.67%
Max Drawdown (1Y) Largest decline over 1 year	—	-2.90%	—
Current Drawdown Current decline from peak	-1.88%	-2.15%	+0.27%
Average Drawdown Average peak-to-trough decline	-1.27%	-1.32%	+0.05%
Ulcer Index Depth and duration of drawdowns from previous peaks	—	0.99%	—

Volatility

Volatility by Period

	IBGC	SPTB	Difference
Volatility (1M) Calculated over the trailing 1-month period	—	1.08%	—
Volatility (6M) Calculated over the trailing 6-month period	—	2.48%	—
Volatility (1Y) Calculated over the trailing 1-year period	8.40%	3.61%	+4.79%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	8.40%	4.41%	+3.99%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	8.40%	4.41%	+3.99%

IBGC vs. SPTB - Expense Ratio Comparison

IBGC has a 0.07% expense ratio, which is higher than SPTB'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

IBGC vs. SPTB - Dividend Comparison

IBGC's dividend yield for the trailing twelve months is around 0.81%, less than SPTB's 4.21% yield.

Position	TTM	2025	2024
IBGC iShares iBonds Dec 2046 Term Treasury ETF	0.81%	0.00%	0.00%
SPTB State Street SPDR Portfolio Treasury ETF	4.21%	4.23%	2.76%

Frequently Asked Questions

Can I hold both IBGC and SPTB in my portfolio?

With a correlation of 0.93, IBGC and SPTB 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 ETF is better, IBGC or SPTB?

On fees, SPTB is cheaper at 0.03% per year. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF is cheaper, IBGC or SPTB?

SPTB is cheaper with a 0.03% expense ratio, compared with 0.07% for IBGC.

Which ETF pays a higher dividend yield, IBGC or SPTB?

SPTB has the higher dividend yield at 4.21%, compared with 0.81% for IBGC.

What is the main difference between IBGC and SPTB?

IBGC tracks ICE 2046 Maturity US Treasury Index, while SPTB tracks Bloomberg U.S. Treasury Index. They also come from different issuers: iShares and State Street. Their fees differ too: 0.07% for IBGC and 0.03% for SPTB.