ACIHX vs. VIGIX

Last updated Jun 5, 2026

ACIHX (American Century Growth Fund G Class) and VIGIX (Vanguard Growth Index Fund Institutional Shares) are both Large Cap Growth Equities funds. ACIHX is actively managed, while VIGIX is passively managed. Over the past 3 years, ACIHX returned 22.42%/yr vs 25.95%/yr for VIGIX. With a 0.99 correlation, they move nearly in lockstep. ACIHX charges 0.01%/yr vs 0.04%/yr for VIGIX.

Performance

ACIHX vs. VIGIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Century Growth Fund G Class (ACIHX) and Vanguard Growth Index Fund Institutional Shares (VIGIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, ACIHX achieves a 7.24% return, which is significantly lower than VIGIX's 9.47% return.

ACIHX

• 1D: -1.57%
• 1M: 5.48%
• YTD: 7.24%
• 6M: 6.26%
• 1Y: 25.16%
• 3Y*: 22.42%
• 5Y*: —
• 10Y*: —

VIGIX

• 1D: -1.23%
• 1M: 5.47%
• YTD: 9.47%
• 6M: 8.60%
• 1Y: 27.36%
• 3Y*: 25.95%
• 5Y*: 15.10%
• 10Y*: 18.25%

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

ACIHX vs. VIGIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022
ACIHX American Century Growth Fund G Class	7.24%	16.26%	27.35%	44.64%	-6.24%
VIGIX Vanguard Growth Index Fund Institutional Shares	9.47%	19.44%	32.68%	46.77%	-8.69%

Correlation

The correlation between ACIHX and VIGIX is 0.99 - 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	0.99
Correlation (3Y) Calculated over the trailing 3-year period	0.99
Correlation (All Time) Calculated using the full available price history since May 17, 2022	0.99

The correlation between ACIHX and VIGIX has been stable across timeframes, ranging from 0.99 to 0.99 - a consistent structural relationship.

Return for Risk

ACIHX vs. VIGIX — Risk / Return Rank

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

ACIHX

ACIHX Risk / Return Rank: 26
ACIHX Sharpe Ratio Rank: 32
ACIHX Sortino Ratio Rank: 29
ACIHX Omega Ratio Rank: 30
ACIHX Calmar Ratio Rank: 19
ACIHX Martin Ratio Rank: 20

VIGIX

VIGIX Risk / Return Rank: 30
VIGIX Sharpe Ratio Rank: 37
VIGIX Sortino Ratio Rank: 33
VIGIX Omega Ratio Rank: 33
VIGIX Calmar Ratio Rank: 21
VIGIX Martin Ratio Rank: 24

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.

ACIHX vs. VIGIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Century Growth Fund G Class (ACIHX) and Vanguard Growth Index Fund Institutional Shares (VIGIX). 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.

	ACIHX	VIGIX	Difference
Sharpe ratio: Return per unit of total volatility	1.64	1.76	-0.12
Sortino ratio: Return per unit of downside risk	2.25	2.40	-0.15
Omega ratio: Gain probability vs. loss probability	1.29	1.31	-0.02
Calmar ratio: Return relative to maximum drawdown	1.58	1.70	-0.12
Martin ratio: Return relative to average drawdown	5.29	5.96	-0.67
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

ACIHX vs. VIGIX - Sharpe Ratio Comparison

The current ACIHX Sharpe Ratio is 1.64, which is comparable to the VIGIX Sharpe Ratio of 1.76. The chart below compares the historical Sharpe Ratios of ACIHX and VIGIX, 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

	ACIHX	VIGIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.64	1.76	-0.12
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	—	0.68	—
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	0.85	—
Sharpe Ratio (All Time) Calculated using the full available price history	1.00	0.47	+0.53

Drawdowns

ACIHX vs. VIGIX - Drawdown Comparison

The maximum ACIHX drawdown since its inception was -24.00%, smaller than the maximum VIGIX drawdown of -56.95%. Use the drawdown chart below to compare losses from any high point for ACIHX and VIGIX.

Drawdown Indicators

	ACIHX	VIGIX	Difference
Max Drawdown Largest peak-to-trough decline	-24.00%	-56.95%	+32.95%
Max Drawdown (1Y) Largest decline over 1 year	-16.40%	-16.51%	+0.11%
Max Drawdown (3Y) Largest decline over 3 years	-24.00%	-23.03%	-0.97%
Max Drawdown (5Y) Largest decline over 5 years	—	-35.62%	—
Max Drawdown (10Y) Largest decline over 10 years	—	-35.62%	—
Current Drawdown Current decline from peak	-2.07%	-1.51%	-0.56%
Average Drawdown Average peak-to-trough decline	-4.89%	-16.27%	+11.38%
Ulcer Index Depth and duration of drawdowns from previous peaks	4.87%	4.68%	+0.19%

Volatility

ACIHX vs. VIGIX - Volatility Comparison

American Century Growth Fund G Class (ACIHX) and Vanguard Growth Index Fund Institutional Shares (VIGIX) have volatilities of 3.93% and 3.92%, respectively, indicating that both stocks experience similar levels of price fluctuations. This suggests that the risk associated with both stocks, as measured by volatility, is nearly the same. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	ACIHX	VIGIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.93%	3.92%	+0.01%
Volatility (6M) Calculated over the trailing 6-month period	12.02%	12.17%	-0.15%
Volatility (1Y) Calculated over the trailing 1-year period	15.80%	15.92%	-0.12%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	21.06%	22.35%	-1.29%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	21.06%	21.59%	-0.53%

ACIHX vs. VIGIX - Expense Ratio Comparison

ACIHX has a 0.01% expense ratio, which is lower than VIGIX's 0.04% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

ACIHX vs. VIGIX - Dividend Comparison

ACIHX's dividend yield for the trailing twelve months is around 14.87%, more than VIGIX's 0.37% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
ACIHX American Century Growth Fund G Class	14.87%	15.95%	5.65%	4.61%	2.86%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
VIGIX Vanguard Growth Index Fund Institutional Shares	0.37%	0.41%	0.47%	0.58%	0.70%	0.48%	0.66%	0.95%	1.32%	1.15%	1.40%	1.31%

Frequently Asked Questions

Can I hold both ACIHX and VIGIX in my portfolio?

With a correlation of 0.99, ACIHX and VIGIX 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, ACIHX or VIGIX?

ACIHX has higher volatility (3.93%) compared to VIGIX (3.92%). In terms of maximum drawdown, ACIHX dropped -24.00% vs VIGIX's -56.95%.

Which has better risk-adjusted returns?

VIGIX currently has the higher Sharpe Ratio (1.76 vs 1.64), 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.