AAAMX vs. VOO

Last updated Jun 23, 2026

AAAMX (American Century One Choice Blend+ 2020 Portfolio) and VOO (Vanguard S&P 500 ETF) are both funds - AAAMX is a Target Retirement Date fund managed by American Century, while VOO is a S&P 500 fund tracking the S&P 500 Index. Over the past 5 years, AAAMX returned 4.43%/yr vs 13.58%/yr for VOO. Their correlation of 0.85 suggests significant overlap in exposure. AAAMX charges 0.57%/yr vs 0.03%/yr for VOO.

Performance

AAAMX vs. VOO - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Century One Choice Blend+ 2020 Portfolio (AAAMX) and Vanguard S&P 500 ETF (VOO). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, AAAMX achieves a 4.29% return, which is significantly lower than VOO's 9.75% return.

AAAMX

• 1D: 0.46%
• 1M: 0.64%
• YTD: 4.29%
• 6M: 4.19%
• 1Y: 12.19%
• 3Y*: 9.35%
• 5Y*: 4.43%
• 10Y*: —

VOO

• 1D: -0.29%
• 1M: 0.08%
• YTD: 9.75%
• 6M: 9.30%
• 1Y: 26.77%
• 3Y*: 21.36%
• 5Y*: 13.58%
• 10Y*: 15.77%

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

AAAMX vs. VOO - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021
AAAMX American Century One Choice Blend+ 2020 Portfolio	4.29%	11.63%	6.87%	10.81%	-13.19%	6.88%
VOO Vanguard S&P 500 ETF	9.75%	17.82%	24.98%	26.32%	-18.17%	24.39%

Correlation

The correlation between AAAMX and VOO is 0.87, indicating a strong positive relationship between their price movements. Combining them offers limited diversification - they tend to fall together during downturns.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.87
Correlation (3Y) Calculated over the trailing 3-year period	0.82
Correlation (5Y) Calculated over the trailing 5-year period	0.85
Correlation (All Time) Calculated using the full available price history since Mar 10, 2021	0.85

The correlation between AAAMX and VOO has been stable across timeframes, ranging from 0.82 to 0.87 - a consistent structural relationship.

Return for Risk

AAAMX vs. VOO — Risk / Return Rank

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

AAAMX

AAAMX Risk / Return Rank: 61
AAAMX Sharpe Ratio Rank: 62
AAAMX Sortino Ratio Rank: 66
AAAMX Omega Ratio Rank: 65
AAAMX Calmar Ratio Rank: 50
AAAMX Martin Ratio Rank: 61

VOO

VOO Risk / Return Rank: 68
VOO Sharpe Ratio Rank: 70
VOO Sortino Ratio Rank: 67
VOO Omega Ratio Rank: 69
VOO Calmar Ratio Rank: 63
VOO Martin Ratio Rank: 74

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.

AAAMX vs. VOO - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Century One Choice Blend+ 2020 Portfolio (AAAMX) and Vanguard S&P 500 ETF (VOO). 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.

	AAAMX	VOO	Difference
Sharpe ratio: Return per unit of total volatility	2.14	2.17	-0.04
Sortino ratio: Return per unit of downside risk	3.09	2.93	+0.16
Omega ratio: Gain probability vs. loss probability	1.41	1.39	+0.01
Calmar ratio: Return relative to maximum drawdown	2.60	3.02	-0.43
Martin ratio: Return relative to average drawdown	11.41	13.58	-2.17

AAAMX vs. VOO - Sharpe Ratio Comparison

The current AAAMX Sharpe Ratio is 2.14, which is comparable to the VOO Sharpe Ratio of 2.17. The chart below compares the historical Sharpe Ratios of AAAMX and VOO, 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

AAAMX vs. VOO - Drawdown Comparison

The maximum AAAMX drawdown since its inception was -19.03%, smaller than the maximum VOO drawdown of -33.99%. Use the drawdown chart below to compare losses from any high point for AAAMX and VOO.

Drawdown Indicators

	AAAMX	VOO	Difference
Max Drawdown Largest peak-to-trough decline	-19.03%	-33.99%	+14.96%
Max Drawdown (1Y) Largest decline over 1 year	-4.72%	-8.90%	+4.18%
Max Drawdown (3Y) Largest decline over 3 years	-6.33%	-18.69%	+12.36%
Max Drawdown (5Y) Largest decline over 5 years	-19.03%	-24.52%	+5.49%
Max Drawdown (10Y) Largest decline over 10 years	—	-33.99%	—
Current Drawdown Current decline from peak	-0.36%	-1.74%	+1.38%
Average Drawdown Average peak-to-trough decline	-4.80%	-3.68%	-1.12%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.07%	1.98%	-0.91%

Volatility

AAAMX vs. VOO - Volatility Comparison

The current volatility for American Century One Choice Blend+ 2020 Portfolio (AAAMX) is 2.19%, while Vanguard S&P 500 ETF (VOO) has a volatility of 4.60%. This indicates that AAAMX experiences smaller price fluctuations and is considered to be less risky than VOO based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	AAAMX	VOO	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.19%	4.60%	-2.41%
Volatility (6M) Calculated over the trailing 6-month period	4.73%	9.73%	-5.00%
Volatility (1Y) Calculated over the trailing 1-year period	5.74%	12.39%	-6.65%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	7.71%	16.90%	-9.19%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	7.60%	18.05%	-10.45%

AAAMX vs. VOO - Expense Ratio Comparison

AAAMX has a 0.57% expense ratio, which is higher than VOO's 0.03% expense ratio.

Dividends

AAAMX vs. VOO - Dividend Comparison

AAAMX's dividend yield for the trailing twelve months is around 2.93%, more than VOO's 1.04% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
AAAMX American Century One Choice Blend+ 2020 Portfolio	2.93%	5.13%	3.20%	2.10%	2.85%	2.28%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
VOO Vanguard S&P 500 ETF	1.04%	1.13%	1.24%	1.46%	1.69%	1.25%	1.54%	1.88%	2.06%	1.78%	2.02%	2.10%

Frequently Asked Questions

Can I hold both AAAMX and VOO in my portfolio?

AAAMX and VOO have a correlation of 0.87, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, AAAMX or VOO?

VOO has higher volatility (4.60%) compared to AAAMX (2.19%). In terms of maximum drawdown, AAAMX dropped -19.03% vs VOO's -33.99%.

Which has better risk-adjusted returns?

VOO currently has the higher Sharpe Ratio (2.17 vs 2.14), 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.