VTBIX vs. FIFZX

Last updated Jun 5, 2026

VTBIX (Vanguard Total Bond Market II Index Fund Investor Shares) and FIFZX (Fidelity Series Bond Index Fund) are both Total Bond Market funds. Over the past 5 years, VTBIX returned -0.09%/yr vs 0.10%/yr for FIFZX. With a 0.97 correlation, they move nearly in lockstep. VTBIX charges 0.09%/yr vs 0.00%/yr for FIFZX.

Performance

VTBIX vs. FIFZX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard Total Bond Market II Index Fund Investor Shares (VTBIX) and Fidelity Series Bond Index Fund (FIFZX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, VTBIX achieves a 0.09% return, which is significantly lower than FIFZX's 0.45% return.

VTBIX

• 1D: -0.21%
• 1M: 0.13%
• YTD: 0.09%
• 6M: 0.21%
• 1Y: 4.37%
• 3Y*: 3.76%
• 5Y*: -0.09%
• 10Y*: 1.42%

FIFZX

• 1D: 0.00%
• 1M: 0.46%
• YTD: 0.45%
• 6M: 0.35%
• 1Y: 5.45%
• 3Y*: 4.06%
• 5Y*: 0.10%
• 10Y*: —

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

VTBIX vs. FIFZX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019
VTBIX Vanguard Total Bond Market II Index Fund Investor Shares	0.09%	7.11%	1.25%	5.03%	-13.18%	-1.88%	7.47%	5.81%
FIFZX Fidelity Series Bond Index Fund	0.45%	7.15%	1.41%	5.54%	-13.46%	-1.96%	7.65%	5.12%

Correlation

The correlation between VTBIX and FIFZX is 0.96 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.96
Correlation (3Y) Calculated over the trailing 3-year period	0.97
Correlation (5Y) Calculated over the trailing 5-year period	0.98
Correlation (All Time) Calculated using the full available price history since Apr 29, 2019	0.97

The correlation between VTBIX and FIFZX has been stable across timeframes, ranging from 0.96 to 0.98 - a consistent structural relationship.

Return for Risk

VTBIX vs. FIFZX — Risk / Return Rank

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

VTBIX

VTBIX Risk / Return Rank: 20
VTBIX Sharpe Ratio Rank: 19
VTBIX Sortino Ratio Rank: 21
VTBIX Omega Ratio Rank: 18
VTBIX Calmar Ratio Rank: 22
VTBIX Martin Ratio Rank: 19

FIFZX

FIFZX Risk / Return Rank: 23
FIFZX Sharpe Ratio Rank: 22
FIFZX Sortino Ratio Rank: 24
FIFZX Omega Ratio Rank: 21
FIFZX Calmar Ratio Rank: 24
FIFZX Martin Ratio Rank: 21

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.

VTBIX vs. FIFZX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard Total Bond Market II Index Fund Investor Shares (VTBIX) and Fidelity Series Bond Index Fund (FIFZX). 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.

	VTBIX	FIFZX	Difference
Sharpe ratio: Return per unit of total volatility	1.26	1.35	-0.08
Sortino ratio: Return per unit of downside risk	1.91	2.05	-0.14
Omega ratio: Gain probability vs. loss probability	1.22	1.24	-0.02
Calmar ratio: Return relative to maximum drawdown	1.74	1.84	-0.10
Martin ratio: Return relative to average drawdown	5.17	5.52	-0.35
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VTBIX vs. FIFZX - Sharpe Ratio Comparison

The current VTBIX Sharpe Ratio is 1.26, which is comparable to the FIFZX Sharpe Ratio of 1.35. The chart below compares the historical Sharpe Ratios of VTBIX and FIFZX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Sharpe Ratios by Period

	VTBIX	FIFZX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.26	1.35	-0.08
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.01	0.02	-0.03
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.29	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.27	0.26	+0.01

Drawdowns

VTBIX vs. FIFZX - Drawdown Comparison

The maximum VTBIX drawdown since its inception was -18.72%, roughly equal to the maximum FIFZX drawdown of -19.27%. Use the drawdown chart below to compare losses from any high point for VTBIX and FIFZX.

Drawdown Indicators

	VTBIX	FIFZX	Difference
Max Drawdown Largest peak-to-trough decline	-18.72%	-19.27%	+0.55%
Max Drawdown (1Y) Largest decline over 1 year	-2.84%	-2.91%	+0.07%
Max Drawdown (3Y) Largest decline over 3 years	-5.98%	-6.12%	+0.14%
Max Drawdown (5Y) Largest decline over 5 years	-18.11%	-18.47%	+0.36%
Max Drawdown (10Y) Largest decline over 10 years	-18.72%	—	—
Current Drawdown Current decline from peak	-3.20%	-2.75%	-0.45%
Average Drawdown Average peak-to-trough decline	-4.42%	-6.70%	+2.28%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.95%	0.97%	-0.02%

Volatility

VTBIX vs. FIFZX - Volatility Comparison

The current volatility for Vanguard Total Bond Market II Index Fund Investor Shares (VTBIX) is 1.31%, while Fidelity Series Bond Index Fund (FIFZX) has a volatility of 1.39%. This indicates that VTBIX experiences smaller price fluctuations and is considered to be less risky than FIFZX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VTBIX	FIFZX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.31%	1.39%	-0.08%
Volatility (6M) Calculated over the trailing 6-month period	2.78%	2.84%	-0.06%
Volatility (1Y) Calculated over the trailing 1-year period	3.91%	3.99%	-0.08%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	5.95%	6.08%	-0.13%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	4.92%	5.63%	-0.71%

VTBIX vs. FIFZX - Expense Ratio Comparison

VTBIX has a 0.09% expense ratio, which is higher than FIFZX's 0.00% 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

VTBIX vs. FIFZX - Dividend Comparison

VTBIX's dividend yield for the trailing twelve months is around 3.99%, which matches FIFZX's 4.00% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FIFZX Fidelity Series Bond Index Fund	4.00%	3.87%	3.66%	3.09%	1.74%	1.42%	3.20%	1.64%	0.00%	0.00%	0.00%	0.00%
VTBIX Vanguard Total Bond Market II Index Fund Investor Shares	3.99%	3.88%	3.70%	2.53%	2.47%	1.75%	3.20%	2.72%	2.51%	2.43%	2.48%	2.64%

Frequently Asked Questions

Can I hold both VTBIX and FIFZX in my portfolio?

With a correlation of 0.96, VTBIX and FIFZX 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 is riskier, VTBIX or FIFZX?

FIFZX has higher volatility (1.39%) compared to VTBIX (1.31%). In terms of maximum drawdown, VTBIX dropped -18.72% vs FIFZX's -19.27%.

Which has better risk-adjusted returns?

FIFZX currently has the higher Sharpe Ratio (1.35 vs 1.26), 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.