AAATX vs. MGK

Last updated Jun 3, 2026

AAATX (American Funds 2010 Target Date Retirement Fund) and MGK (Vanguard Mega Cap Growth ETF) are both funds - AAATX is a Target Retirement Date fund managed by American Funds, while MGK is a Large Cap Growth Equities fund tracking the CRSP US Mega Cap Growth Index. Over the past 10 years, AAATX returned 6.20%/yr vs 19.37%/yr for MGK. Their correlation of 0.80 suggests significant overlap in exposure. AAATX charges 0.34%/yr vs 0.05%/yr for MGK.

Performance

AAATX vs. MGK - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Funds 2010 Target Date Retirement Fund (AAATX) and Vanguard Mega Cap Growth ETF (MGK). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, AAATX achieves a 3.76% return, which is significantly lower than MGK's 11.27% return. Over the past 10 years, AAATX has underperformed MGK with an annualized return of 6.20%, while MGK has yielded a comparatively higher 19.37% annualized return.

AAATX

• 1D: -0.16%
• 1M: 0.87%
• YTD: 3.76%
• 6M: 4.45%
• 1Y: 11.67%
• 3Y*: 10.06%
• 5Y*: 5.04%
• 10Y*: 6.20%

MGK

• 1D: -0.30%
• 1M: 8.29%
• YTD: 11.27%
• 6M: 10.68%
• 1Y: 32.46%
• 3Y*: 27.25%
• 5Y*: 16.84%
• 10Y*: 19.37%

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

AAATX vs. MGK - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
AAATX American Funds 2010 Target Date Retirement Fund	3.76%	12.73%	7.83%	8.44%	-9.50%	9.02%	8.84%	13.51%	-2.85%	9.97%
MGK Vanguard Mega Cap Growth ETF	11.27%	20.67%	32.94%	51.67%	-33.59%	28.58%	41.01%	37.38%	-2.91%	29.49%

Correlation

The correlation between AAATX and MGK is 0.60, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.60
Correlation (3Y) Calculated over the trailing 3-year period	0.62
Correlation (5Y) Calculated over the trailing 5-year period	0.69
Correlation (10Y) Calculated over the trailing 10-year period	0.73
Correlation (All Time) Calculated using the full available price history since Dec 28, 2007	0.80

Over the past year, the correlation between AAATX and MGK has dropped to 0.60 - well below their long-term average of 0.80, suggesting their price drivers have been diverging.

Return for Risk

AAATX vs. MGK — Risk / Return Rank

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

AAATX

AAATX Risk / Return Rank: 65
AAATX Sharpe Ratio Rank: 72
AAATX Sortino Ratio Rank: 74
AAATX Omega Ratio Rank: 73
AAATX Calmar Ratio Rank: 49
AAATX Martin Ratio Rank: 57

MGK

MGK Risk / Return Rank: 51
MGK Sharpe Ratio Rank: 59
MGK Sortino Ratio Rank: 56
MGK Omega Ratio Rank: 56
MGK Calmar Ratio Rank: 40
MGK Martin Ratio Rank: 43

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.

AAATX vs. MGK - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Funds 2010 Target Date Retirement Fund (AAATX) and Vanguard Mega Cap Growth ETF (MGK). 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.

	AAATX	MGK	Difference
Sharpe ratio Return per unit of total volatility	2.46	2.02	+0.45
Sortino ratio Return per unit of downside risk	3.58	2.71	+0.87
Omega ratio Gain probability vs. loss probability	1.48	1.35	+0.13
Calmar ratio Return relative to maximum drawdown	2.70	2.00	+0.70
Martin ratio Return relative to average drawdown	11.59	6.90	+4.70
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

AAATX vs. MGK - Sharpe Ratio Comparison

The current AAATX Sharpe Ratio is 2.46, which is comparable to the MGK Sharpe Ratio of 2.02. The chart below compares the historical Sharpe Ratios of AAATX and MGK, 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

	AAATX	MGK	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.46	2.02	+0.45
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.78	0.75	+0.03
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.93	0.89	+0.04
Sharpe Ratio (All Time) Calculated using the full available price history	0.56	0.66	-0.10

Drawdowns

AAATX vs. MGK - Drawdown Comparison

The maximum AAATX drawdown since its inception was -40.44%, smaller than the maximum MGK drawdown of -47.97%. Use the drawdown chart below to compare losses from any high point for AAATX and MGK.

Drawdown Indicators

	AAATX	MGK	Difference
Max Drawdown Largest peak-to-trough decline	-40.44%	-47.97%	+7.53%
Max Drawdown (1Y) Largest decline over 1 year	-4.42%	-16.85%	+12.43%
Max Drawdown (3Y) Largest decline over 3 years	-5.57%	-23.36%	+17.79%
Max Drawdown (5Y) Largest decline over 5 years	-14.99%	-36.01%	+21.02%
Max Drawdown (10Y) Largest decline over 10 years	-15.13%	-36.01%	+20.88%
Current Drawdown Current decline from peak	-0.16%	-0.30%	+0.14%
Average Drawdown Average peak-to-trough decline	-4.35%	-7.47%	+3.12%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.03%	4.89%	-3.86%

Volatility

AAATX vs. MGK - Volatility Comparison

The current volatility for American Funds 2010 Target Date Retirement Fund (AAATX) is 1.54%, while Vanguard Mega Cap Growth ETF (MGK) has a volatility of 3.75%. This indicates that AAATX experiences smaller price fluctuations and is considered to be less risky than MGK based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	AAATX	MGK	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.54%	3.75%	-2.21%
Volatility (6M) Calculated over the trailing 6-month period	3.83%	12.32%	-8.49%
Volatility (1Y) Calculated over the trailing 1-year period	4.81%	16.20%	-11.39%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	6.53%	22.63%	-16.10%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	6.68%	21.88%	-15.20%

AAATX vs. MGK - Expense Ratio Comparison

AAATX has a 0.34% expense ratio, which is higher than MGK's 0.05% expense ratio.

Dividends

AAATX vs. MGK - Dividend Comparison

AAATX's dividend yield for the trailing twelve months is around 6.59%, more than MGK's 0.31% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
AAATX American Funds 2010 Target Date Retirement Fund	6.59%	6.84%	5.16%	3.53%	3.41%	3.78%	3.72%	3.48%	3.79%	2.51%	2.67%	4.60%
MGK Vanguard Mega Cap Growth ETF	0.31%	0.35%	0.43%	0.50%	0.70%	0.41%	0.65%	0.85%	1.12%	1.23%	1.53%	1.43%

Frequently Asked Questions

Can I hold both AAATX and MGK in my portfolio?

AAATX and MGK have a correlation of 0.60, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, AAATX or MGK?

MGK has higher volatility (3.75%) compared to AAATX (1.54%). In terms of maximum drawdown, AAATX dropped -40.44% vs MGK's -47.97%.

Which has better risk-adjusted returns?

AAATX currently has the higher Sharpe Ratio (2.46 vs 2.02), 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.