AAMTX vs. VTSAX

Last updated Jun 23, 2026

AAMTX (American Funds 2055 Target Date Retirement Fund) and VTSAX (Vanguard Total Stock Market Index Fund Admiral Shares) are both mutual funds - AAMTX is a Target Retirement Date fund managed by American Funds, while VTSAX is a Large Cap Blend Equities fund managed by Vanguard. Over the past 10 years, AAMTX returned 12.08%/yr vs 15.06%/yr for VTSAX. With a 0.96 correlation, they move nearly in lockstep. AAMTX charges 0.33%/yr vs 0.04%/yr for VTSAX.

Performance

AAMTX vs. VTSAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Funds 2055 Target Date Retirement Fund (AAMTX) and Vanguard Total Stock Market Index Fund Admiral Shares (VTSAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

The year-to-date returns for both stocks are quite close, with AAMTX having a 10.83% return and VTSAX slightly lower at 10.72%. Over the past 10 years, AAMTX has underperformed VTSAX with an annualized return of 12.08%, while VTSAX has yielded a comparatively higher 15.06% annualized return.

AAMTX

• 1D: 1.17%
• 1M: 2.39%
• YTD: 10.83%
• 6M: 10.82%
• 1Y: 25.43%
• 3Y*: 18.37%
• 5Y*: 9.93%
• 10Y*: 12.08%

VTSAX

• 1D: 1.14%
• 1M: 0.90%
• YTD: 10.72%
• 6M: 9.93%
• 1Y: 27.56%
• 3Y*: 20.66%
• 5Y*: 12.87%
• 10Y*: 15.06%

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

AAMTX vs. VTSAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
AAMTX American Funds 2055 Target Date Retirement Fund	10.83%	20.37%	15.16%	21.03%	-19.75%	16.94%	19.06%	24.60%	-5.95%	22.20%
VTSAX Vanguard Total Stock Market Index Fund Admiral Shares	10.72%	17.12%	23.23%	26.51%	-19.52%	25.72%	20.98%	30.79%	-5.18%	21.16%

Correlation

The correlation between AAMTX and VTSAX is 0.95 - 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	0.95
Correlation (3Y) Calculated over the trailing 3-year period	0.96
Correlation (5Y) Calculated over the trailing 5-year period	0.97
Correlation (10Y) Calculated over the trailing 10-year period	0.96
Correlation (All Time) Calculated using the full available price history since Feb 2, 2010	0.96

The correlation between AAMTX and VTSAX has been stable across timeframes, ranging from 0.95 to 0.97 - a consistent structural relationship.

Return for Risk

AAMTX vs. VTSAX — Risk / Return Rank

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

AAMTX

AAMTX Risk / Return Rank: 54
AAMTX Sharpe Ratio Rank: 53
AAMTX Sortino Ratio Rank: 51
AAMTX Omega Ratio Rank: 54
AAMTX Calmar Ratio Rank: 50
AAMTX Martin Ratio Rank: 62

VTSAX

VTSAX Risk / Return Rank: 65
VTSAX Sharpe Ratio Rank: 63
VTSAX Sortino Ratio Rank: 57
VTSAX Omega Ratio Rank: 58
VTSAX Calmar Ratio Rank: 70
VTSAX Martin Ratio Rank: 80

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.

AAMTX vs. VTSAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Funds 2055 Target Date Retirement Fund (AAMTX) and Vanguard Total Stock Market Index Fund Admiral Shares (VTSAX). 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.

	AAMTX	VTSAX	Difference
Sharpe ratio: Return per unit of total volatility	1.99	2.14	-0.15
Sortino ratio: Return per unit of downside risk	2.76	2.90	-0.14
Omega ratio: Gain probability vs. loss probability	1.37	1.38	-0.02
Calmar ratio: Return relative to maximum drawdown	2.59	3.07	-0.48
Martin ratio: Return relative to average drawdown	11.52	13.77	-2.26

AAMTX vs. VTSAX - Sharpe Ratio Comparison

The current AAMTX Sharpe Ratio is 1.99, which is comparable to the VTSAX Sharpe Ratio of 2.14. The chart below compares the historical Sharpe Ratios of AAMTX and VTSAX, 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

AAMTX vs. VTSAX - Drawdown Comparison

The maximum AAMTX drawdown since its inception was -29.32%, smaller than the maximum VTSAX drawdown of -55.33%. Use the drawdown chart below to compare losses from any high point for AAMTX and VTSAX.

Drawdown Indicators

	AAMTX	VTSAX	Difference
Max Drawdown Largest peak-to-trough decline	-29.32%	-55.33%	+26.01%
Max Drawdown (1Y) Largest decline over 1 year	-9.71%	-8.92%	-0.79%
Max Drawdown (3Y) Largest decline over 3 years	-15.39%	-19.36%	+3.97%
Max Drawdown (5Y) Largest decline over 5 years	-27.34%	-25.36%	-1.98%
Max Drawdown (10Y) Largest decline over 10 years	-29.32%	-34.97%	+5.65%
Current Drawdown Current decline from peak	-0.03%	-1.13%	+1.10%
Average Drawdown Average peak-to-trough decline	-4.27%	-8.99%	+4.72%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.18%	1.99%	+0.19%

Volatility

AAMTX vs. VTSAX - Volatility Comparison

American Funds 2055 Target Date Retirement Fund (AAMTX) has a higher volatility of 5.13% compared to Vanguard Total Stock Market Index Fund Admiral Shares (VTSAX) at 4.88%. This indicates that AAMTX's price experiences larger fluctuations and is considered to be riskier than VTSAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	AAMTX	VTSAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	5.13%	4.88%	+0.25%
Volatility (6M) Calculated over the trailing 6-month period	10.49%	10.11%	+0.38%
Volatility (1Y) Calculated over the trailing 1-year period	12.66%	12.80%	-0.14%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	14.72%	17.45%	-2.73%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	15.09%	18.45%	-3.36%

AAMTX vs. VTSAX - Expense Ratio Comparison

AAMTX has a 0.33% expense ratio, which is higher than VTSAX's 0.04% expense ratio.

Dividends

AAMTX vs. VTSAX - Dividend Comparison

AAMTX's dividend yield for the trailing twelve months is around 5.14%, more than VTSAX's 1.01% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
AAMTX American Funds 2055 Target Date Retirement Fund	5.14%	5.70%	3.22%	2.22%	6.92%	4.15%	2.98%	3.92%	4.46%	2.18%	3.19%	4.06%
VTSAX Vanguard Total Stock Market Index Fund Admiral Shares	1.01%	1.11%	1.26%	1.42%	1.65%	1.20%	1.41%	1.76%	2.03%	1.71%	1.92%	1.98%

Frequently Asked Questions

Can I hold both AAMTX and VTSAX in my portfolio?

With a correlation of 0.95, AAMTX and VTSAX 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, AAMTX or VTSAX?

AAMTX has higher volatility (5.13%) compared to VTSAX (4.88%). In terms of maximum drawdown, AAMTX dropped -29.32% vs VTSAX's -55.33%.

Which has better risk-adjusted returns?

VTSAX currently has the higher Sharpe Ratio (2.14 vs 1.99), 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.