TBUX vs. FXAIX

Last updated Jun 13, 2026

TBUX (T. Rowe Price Ultra Short-Term Bond ETF) and FXAIX (Fidelity 500 Index Fund) are both funds - TBUX is a Ultrashort Bond fund actively managed by T. Rowe Price, while FXAIX is a S&P 500 fund tracking the S&P 500 Index. TBUX is actively managed, while FXAIX is passively managed. Over the past 3 years, TBUX returned 5.89%/yr vs 21.06%/yr for FXAIX. At a 0.10 correlation, their price movements are largely independent. TBUX charges 0.17%/yr vs 0.02%/yr for FXAIX.

Performance

TBUX vs. FXAIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in T. Rowe Price Ultra Short-Term Bond ETF (TBUX) and Fidelity 500 Index Fund (FXAIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, TBUX achieves a 1.83% return, which is significantly lower than FXAIX's 8.59% return.

TBUX

• 1D: 0.00%
• 1M: 0.39%
• YTD: 1.83%
• 6M: 2.14%
• 1Y: 4.81%
• 3Y*: 5.89%
• 5Y*: —
• 10Y*: —

FXAIX

• 1D: 1.76%
• 1M: -0.55%
• YTD: 8.59%
• 6M: 8.94%
• 1Y: 23.79%
• 3Y*: 21.06%
• 5Y*: 13.34%
• 10Y*: 15.44%

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

TBUX vs. FXAIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021
TBUX T. Rowe Price Ultra Short-Term Bond ETF	1.83%	5.37%	6.38%	6.39%	-0.13%	-0.25%
FXAIX Fidelity 500 Index Fund	8.59%	17.84%	25.01%	26.29%	-18.14%	9.90%

Correlation

The correlation between TBUX and FXAIX is 0.20, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.20
Correlation (3Y) Calculated over the trailing 3-year period	0.09
Correlation (All Time) Calculated using the full available price history since Sep 29, 2021	0.10

The correlation between TBUX and FXAIX shifts across timeframes, from 0.09 (3 years) to 0.20 (1 year), reflecting how their relationship changes across market environments.

Return for Risk

TBUX vs. FXAIX — Risk / Return Rank

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

TBUX

TBUX Risk / Return Rank: 99
TBUX Sharpe Ratio Rank: 99
TBUX Sortino Ratio Rank: 99
TBUX Omega Ratio Rank: 99
TBUX Calmar Ratio Rank: 99
TBUX Martin Ratio Rank: 99

FXAIX

FXAIX Risk / Return Rank: 73
FXAIX Sharpe Ratio Rank: 72
FXAIX Sortino Ratio Rank: 68
FXAIX Omega Ratio Rank: 69
FXAIX Calmar Ratio Rank: 73
FXAIX Martin Ratio Rank: 84

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.

TBUX vs. FXAIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for T. Rowe Price Ultra Short-Term Bond ETF (TBUX) and Fidelity 500 Index Fund (FXAIX). 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.

	TBUX	FXAIX	Difference
Sharpe ratio: Return per unit of total volatility	7.19	1.97	+5.21
Sortino ratio: Return per unit of downside risk	14.51	2.67	+11.84
Omega ratio: Gain probability vs. loss probability	3.12	1.36	+1.76
Calmar ratio: Return relative to maximum drawdown	48.17	2.74	+45.42
Martin ratio: Return relative to average drawdown	182.82	12.46	+170.37

TBUX vs. FXAIX - Sharpe Ratio Comparison

The current TBUX Sharpe Ratio is 7.19, which is higher than the FXAIX Sharpe Ratio of 1.97. The chart below compares the historical Sharpe Ratios of TBUX and FXAIX, 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

TBUX vs. FXAIX - Drawdown Comparison

The maximum TBUX drawdown since its inception was -1.82%, smaller than the maximum FXAIX drawdown of -33.79%. Use the drawdown chart below to compare losses from any high point for TBUX and FXAIX.

Drawdown Indicators

	TBUX	FXAIX	Difference
Max Drawdown Largest peak-to-trough decline	-1.82%	-33.79%	+31.97%
Max Drawdown (1Y) Largest decline over 1 year	-0.10%	-8.89%	+8.79%
Max Drawdown (3Y) Largest decline over 3 years	-0.33%	-18.76%	+18.43%
Max Drawdown (5Y) Largest decline over 5 years	—	-24.50%	—
Max Drawdown (10Y) Largest decline over 10 years	—	-33.79%	—
Current Drawdown Current decline from peak	0.00%	-2.79%	+2.79%
Average Drawdown Average peak-to-trough decline	-0.28%	-3.79%	+3.51%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.03%	1.95%	-1.92%

Volatility

TBUX vs. FXAIX - Volatility Comparison

The current volatility for T. Rowe Price Ultra Short-Term Bond ETF (TBUX) is 0.22%, while Fidelity 500 Index Fund (FXAIX) has a volatility of 4.44%. This indicates that TBUX experiences smaller price fluctuations and is considered to be less risky than FXAIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	TBUX	FXAIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.22%	4.44%	-4.22%
Volatility (6M) Calculated over the trailing 6-month period	0.46%	9.70%	-9.24%
Volatility (1Y) Calculated over the trailing 1-year period	0.67%	12.37%	-11.70%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	1.07%	16.99%	-15.92%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	1.07%	18.10%	-17.03%

TBUX vs. FXAIX - Expense Ratio Comparison

TBUX has a 0.17% expense ratio, which is higher than FXAIX's 0.02% 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

TBUX vs. FXAIX - Dividend Comparison

TBUX's dividend yield for the trailing twelve months is around 4.48%, more than FXAIX's 1.06% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FXAIX Fidelity 500 Index Fund	1.06%	1.11%	1.25%	1.45%	1.69%	1.22%	1.60%	2.06%	2.72%	1.97%	2.52%	2.83%
TBUX T. Rowe Price Ultra Short-Term Bond ETF	4.48%	4.67%	5.39%	4.66%	2.58%	0.27%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both TBUX and FXAIX in my portfolio?

TBUX and FXAIX have a correlation of 0.20, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, TBUX or FXAIX?

FXAIX has higher volatility (4.44%) compared to TBUX (0.22%). In terms of maximum drawdown, TBUX dropped -1.82% vs FXAIX's -33.79%.

Which has better risk-adjusted returns?

TBUX currently has the higher Sharpe Ratio (7.19 vs 1.97), 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.