SUB vs. FLOT

Last updated Jun 23, 2026

SUB (iShares Short-Term National Muni Bond ETF) and FLOT (iShares Floating Rate Bond ETF) are both exchange-traded funds - SUB is a Municipal Bonds fund tracking the ICE Short Maturity AMT-Free US National Municipal Index - Benchmark TR Gross, while FLOT is a Ultrashort Bond fund tracking the Bloomberg US Floating Rate Note < 5 Years Index. Both are passively managed. Over the past 10 years, SUB returned 1.46%/yr vs 3.04%/yr for FLOT. At a 0.02 correlation, their price movements are largely independent. SUB charges 0.07%/yr vs 0.15%/yr for FLOT.

Performance

SUB vs. FLOT - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares Short-Term National Muni Bond ETF (SUB) and iShares Floating Rate Bond ETF (FLOT). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, SUB achieves a 0.93% return, which is significantly lower than FLOT's 2.03% return. Over the past 10 years, SUB has underperformed FLOT with an annualized return of 1.46%, while FLOT has yielded a comparatively higher 3.04% annualized return.

SUB

• 1D: 0.00%
• 1M: 0.52%
• YTD: 0.93%
• 6M: 1.10%
• 1Y: 2.93%
• 3Y*: 3.08%
• 5Y*: 1.51%
• 10Y*: 1.46%

FLOT

• 1D: 0.02%
• 1M: 0.33%
• YTD: 2.03%
• 6M: 2.19%
• 1Y: 4.78%
• 3Y*: 5.60%
• 5Y*: 4.22%
• 10Y*: 3.04%

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

SUB vs. FLOT - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
SUB iShares Short-Term National Muni Bond ETF	0.93%	3.64%	2.17%	2.91%	-2.05%	0.03%	2.51%	2.93%	1.85%	0.75%
FLOT iShares Floating Rate Bond ETF	2.03%	4.91%	6.53%	6.43%	1.28%	0.45%	0.87%	3.97%	1.48%	1.65%

Correlation

The correlation between SUB and FLOT is 0.10, meaning there is essentially no relationship between their price movements. Each responds to its own set of market drivers, making them strong candidates for combining in a diversified portfolio.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.10
Correlation (3Y) Calculated over the trailing 3-year period	0.11
Correlation (5Y) Calculated over the trailing 5-year period	0.11
Correlation (10Y) Calculated over the trailing 10-year period	0.03
Correlation (All Time) Calculated using the full available price history since Jun 17, 2011	0.02

Return for Risk

SUB vs. FLOT — Risk / Return Rank

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

SUB

SUB Risk / Return Rank: 82
SUB Sharpe Ratio Rank: 90
SUB Sortino Ratio Rank: 92
SUB Omega Ratio Rank: 94
SUB Calmar Ratio Rank: 74
SUB Martin Ratio Rank: 60

FLOT

FLOT Risk / Return Rank: 98
FLOT Sharpe Ratio Rank: 99
FLOT Sortino Ratio Rank: 99
FLOT Omega Ratio Rank: 99
FLOT Calmar Ratio Rank: 97
FLOT Martin Ratio Rank: 99

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.

SUB vs. FLOT - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares Short-Term National Muni Bond ETF (SUB) and iShares Floating Rate Bond ETF (FLOT). 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.

Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.

	SUB	FLOT	Difference
Sharpe ratio: Return per unit of total volatility	2.92	6.42	-3.50
Sortino ratio: Return per unit of downside risk	4.21	11.58	-7.36
Omega ratio: Gain probability vs. loss probability	1.64	3.15	-1.51
Calmar ratio: Return relative to maximum drawdown	3.65	11.13	-7.48
Martin ratio: Return relative to average drawdown	10.32	103.02	-92.70

SUB vs. FLOT - Sharpe Ratio Comparison

The current SUB Sharpe Ratio is 2.92, which is lower than the FLOT Sharpe Ratio of 6.42. The chart below compares the historical Sharpe Ratios of SUB and FLOT, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Drawdowns

SUB vs. FLOT - Drawdown Comparison

The maximum SUB drawdown since its inception was -9.46%, smaller than the maximum FLOT drawdown of -13.54%. Use the drawdown chart below to compare losses from any high point for SUB and FLOT.

Drawdown Indicators

	SUB	FLOT	Difference
Max Drawdown Largest peak-to-trough decline	-9.46%	-13.54%	+4.08%
Max Drawdown (1Y) Largest decline over 1 year	-0.81%	-0.43%	-0.38%
Max Drawdown (3Y) Largest decline over 3 years	-1.23%	-1.57%	+0.34%
Max Drawdown (5Y) Largest decline over 5 years	-4.35%	-2.36%	-1.99%
Max Drawdown (10Y) Largest decline over 10 years	-9.46%	-13.54%	+4.08%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-0.91%	-0.21%	-0.70%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.28%	0.05%	+0.23%

Volatility

SUB vs. FLOT - Volatility Comparison

iShares Short-Term National Muni Bond ETF (SUB) has a higher volatility of 0.25% compared to iShares Floating Rate Bond ETF (FLOT) at 0.21%. This indicates that SUB's price experiences larger fluctuations and is considered to be riskier than FLOT based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	SUB	FLOT	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.25%	0.21%	+0.04%
Volatility (6M) Calculated over the trailing 6-month period	0.80%	0.63%	+0.17%
Volatility (1Y) Calculated over the trailing 1-year period	1.01%	0.75%	+0.26%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	1.64%	1.78%	-0.14%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	2.60%	4.15%	-1.55%

SUB vs. FLOT - Expense Ratio Comparison

SUB has a 0.07% expense ratio, which is lower than FLOT's 0.15% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

SUB vs. FLOT - Dividend Comparison

SUB's dividend yield for the trailing twelve months is around 2.52%, less than FLOT's 4.53% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FLOT iShares Floating Rate Bond ETF	4.53%	4.84%	5.82%	5.66%	2.06%	0.43%	1.25%	2.78%	2.41%	1.46%	0.97%	0.53%
SUB iShares Short-Term National Muni Bond ETF	2.52%	2.42%	2.10%	1.73%	0.86%	0.72%	1.23%	1.58%	1.32%	0.95%	0.75%	0.77%

Frequently Asked Questions

Can I hold both SUB and FLOT in my portfolio?

SUB and FLOT have a correlation of 0.10, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, SUB or FLOT?

SUB has higher volatility (0.25%) compared to FLOT (0.21%). In terms of maximum drawdown, SUB dropped -9.46% vs FLOT's -13.54%.

Which ETF is better, SUB or FLOT?

On 10-year performance, FLOT leads with 3.04% vs 1.46% for SUB. On fees, SUB is cheaper at 0.07% per year. Their volatility is very similar. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF has performed better, SUB or FLOT?

Over the 10-year period, FLOT has performed better with a 3.04% return vs 1.46%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

Which ETF is cheaper, SUB or FLOT?

SUB is cheaper with a 0.07% expense ratio, compared with 0.15% for FLOT.

Which ETF pays a higher dividend yield, SUB or FLOT?

FLOT has the higher dividend yield at 4.53%, compared with 2.52% for SUB.

What is the main difference between SUB and FLOT?

SUB is categorized as Municipal Bonds, while FLOT is Ultrashort Bond. SUB tracks ICE Short Maturity AMT-Free US National Municipal Index - Benchmark TR Gross, while FLOT tracks Bloomberg US Floating Rate Note < 5 Years Index. Their fees differ too: 0.07% for SUB and 0.15% for FLOT.

Which has better risk-adjusted returns?

FLOT currently has the higher Sharpe Ratio (6.42 vs 2.92), 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.