MGTIX vs. ACIHX

Last updated Apr 1, 2026

Compare and contrast key facts about MFS Massachusetts Investors Growth Stock Fund (MGTIX) and American Century Growth Fund G Class (ACIHX).

MGTIX is managed by MFS. It was launched on Jan 1, 1932. ACIHX is an actively managed fund by American Century. It was launched on Mar 1, 2022.

Performance

MGTIX vs. ACIHX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in MFS Massachusetts Investors Growth Stock Fund (MGTIX) and American Century Growth Fund G Class (ACIHX). The values are adjusted to include any dividend payments, if applicable.

MGTIX vs. ACIHX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022
MGTIX MFS Massachusetts Investors Growth Stock Fund	-11.87%	10.23%	27.38%	24.40%	-2.36%
ACIHX American Century Growth Fund G Class	-13.30%	16.26%	27.35%	44.64%	-6.24%

Returns By Period

In the year-to-date period, MGTIX achieves a -11.87% return, which is significantly higher than ACIHX's -13.30% return.

MGTIX

• 1D: -0.21%
• 1M: -9.02%
• YTD: -11.87%
• 6M: -10.66%
• 1Y: 2.34%
• 3Y*: 12.60%
• 5Y*: 8.76%
• 10Y*: 13.59%

ACIHX

• 1D: -0.39%
• 1M: -8.72%
• YTD: -13.30%
• 6M: -12.27%
• 1Y: 13.26%
• 3Y*: 17.20%
• 5Y*: —
• 10Y*: —

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

MGTIX vs. ACIHX - Expense Ratio Comparison

MGTIX has a 0.45% expense ratio, which is higher than ACIHX's 0.01% expense ratio.

MGTIX

MFS Massachusetts Investors Growth Stock Fund

ACIHX

American Century Growth Fund G Class

Return for Risk

MGTIX vs. ACIHX — Risk / Return Rank

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

MGTIX

MGTIX Risk / Return Rank: 8
MGTIX Sharpe Ratio Rank: 8
MGTIX Sortino Ratio Rank: 8
MGTIX Omega Ratio Rank: 8
MGTIX Calmar Ratio Rank: 7
MGTIX Martin Ratio Rank: 7

ACIHX

ACIHX Risk / Return Rank: 23
ACIHX Sharpe Ratio Rank: 23
ACIHX Sortino Ratio Rank: 27
ACIHX Omega Ratio Rank: 25
ACIHX Calmar Ratio Rank: 21
ACIHX 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.

MGTIX vs. ACIHX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for MFS Massachusetts Investors Growth Stock Fund (MGTIX) and American Century Growth Fund G Class (ACIHX). 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.

	MGTIX	ACIHX	Difference
Sharpe ratio Return per unit of total volatility	0.16	0.59	-0.44
Sortino ratio Return per unit of downside risk	0.35	1.02	-0.66
Omega ratio Gain probability vs. loss probability	1.05	1.14	-0.09
Calmar ratio Return relative to maximum drawdown	0.06	0.63	-0.57
Martin ratio Return relative to average drawdown	0.21	2.21	-2.01
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

MGTIX vs. ACIHX - Sharpe Ratio Comparison

The current MGTIX Sharpe Ratio is 0.16, which is lower than the ACIHX Sharpe Ratio of 0.59. The chart below compares the historical Sharpe Ratios of MGTIX and ACIHX, offering insights into how both investments have performed under varying market conditions. These values are calculated using daily returns over the previous 12 months.

Sharpe Ratios by Period

	MGTIX	ACIHX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.16	0.59	-0.44
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.50	—	—
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.75	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.47	0.73	-0.27

Correlation

The correlation between MGTIX and ACIHX is 0.91, which is considered to be high. That indicates a strong positive relationship between their price movements. Having highly-correlated positions in a portfolio may signal a lack of diversification, potentially leading to increased risk during market downturns.

Dividends

MGTIX vs. ACIHX - Dividend Comparison

MGTIX's dividend yield for the trailing twelve months is around 12.57%, less than ACIHX's 18.39% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MGTIX MFS Massachusetts Investors Growth Stock Fund	12.57%	11.08%	16.84%	4.17%	4.59%	10.30%	7.43%	7.38%	10.72%	6.83%	5.00%	6.61%
ACIHX American Century Growth Fund G Class	18.39%	15.95%	5.65%	4.61%	2.86%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%

Drawdowns

MGTIX vs. ACIHX - Drawdown Comparison

The maximum MGTIX drawdown since its inception was -60.05%, which is greater than ACIHX's maximum drawdown of -24.00%. Use the drawdown chart below to compare losses from any high point for MGTIX and ACIHX.

Drawdown Indicators

	MGTIX	ACIHX	Difference
Max Drawdown Largest peak-to-trough decline	-60.05%	-24.00%	-36.05%
Max Drawdown (1Y) Largest decline over 1 year	-13.71%	-16.40%	+2.69%
Max Drawdown (5Y) Largest decline over 5 years	-26.52%	—	—
Max Drawdown (10Y) Largest decline over 10 years	-32.42%	—	—
Current Drawdown Current decline from peak	-13.71%	-16.40%	+2.69%
Average Drawdown Average peak-to-trough decline	-17.20%	-4.95%	-12.25%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.75%	4.68%	-0.93%

Volatility

MGTIX vs. ACIHX - Volatility Comparison

The current volatility for MFS Massachusetts Investors Growth Stock Fund (MGTIX) is 4.34%, while American Century Growth Fund G Class (ACIHX) has a volatility of 5.43%. This indicates that MGTIX experiences smaller price fluctuations and is considered to be less risky than ACIHX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MGTIX	ACIHX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.34%	5.43%	-1.09%
Volatility (6M) Calculated over the trailing 6-month period	9.34%	12.03%	-2.69%
Volatility (1Y) Calculated over the trailing 1-year period	17.64%	22.42%	-4.78%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.44%	21.21%	-3.77%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.16%	21.21%	-3.05%