CPOAX vs. VPMCX

Last updated Jun 4, 2026

CPOAX (Morgan Stanley Insight A) and VPMCX (Vanguard PRIMECAP Fund Investor Shares) are both Large Cap Growth Equities funds. Over the past 10 years, CPOAX returned 17.14%/yr vs 17.57%/yr for VPMCX. A 0.79 correlation means they provide meaningful diversification when combined. CPOAX charges 1.15%/yr vs 0.38%/yr for VPMCX.

Performance

CPOAX vs. VPMCX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Morgan Stanley Insight A (CPOAX) and Vanguard PRIMECAP Fund Investor Shares (VPMCX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, CPOAX achieves a 4.60% return, which is significantly lower than VPMCX's 25.40% return. Both investments have delivered pretty close results over the past 10 years, with CPOAX having a 17.14% annualized return and VPMCX not far ahead at 17.57%.

CPOAX

• 1D: -1.26%
• 1M: 6.92%
• YTD: 4.60%
• 6M: 1.21%
• 1Y: 13.31%
• 3Y*: 29.62%
• 5Y*: 0.26%
• 10Y*: 17.14%

VPMCX

• 1D: 0.35%
• 1M: 12.86%
• YTD: 25.40%
• 6M: 26.79%
• 1Y: 58.79%
• 3Y*: 28.00%
• 5Y*: 16.44%
• 10Y*: 17.57%

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

CPOAX vs. VPMCX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
CPOAX Morgan Stanley Insight A	4.60%	18.91%	46.35%	52.72%	-61.02%	-6.83%	115.86%	33.08%	11.94%	48.40%
VPMCX Vanguard PRIMECAP Fund Investor Shares	25.40%	29.60%	13.23%	28.16%	-15.22%	21.64%	17.16%	27.78%	-1.99%	28.17%

Correlation

The correlation between CPOAX and VPMCX is 0.58, 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	0.58
Correlation (3Y) Calculated over the trailing 3-year period	0.67
Correlation (5Y) Calculated over the trailing 5-year period	0.69
Correlation (10Y) Calculated over the trailing 10-year period	0.68
Correlation (All Time) Calculated using the full available price history since Jul 29, 1997	0.79

Over the past year, the correlation between CPOAX and VPMCX has dropped to 0.58 - well below their long-term average of 0.79, suggesting their price drivers have been diverging.

Return for Risk

CPOAX vs. VPMCX — Risk / Return Rank

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

CPOAX

CPOAX Risk / Return Rank: 6
CPOAX Sharpe Ratio Rank: 6
CPOAX Sortino Ratio Rank: 7
CPOAX Omega Ratio Rank: 7
CPOAX Calmar Ratio Rank: 5
CPOAX Martin Ratio Rank: 5

VPMCX

VPMCX Risk / Return Rank: 94
VPMCX Sharpe Ratio Rank: 97
VPMCX Sortino Ratio Rank: 95
VPMCX Omega Ratio Rank: 91
VPMCX Calmar Ratio Rank: 93
VPMCX Martin Ratio Rank: 96

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.

CPOAX vs. VPMCX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Morgan Stanley Insight A (CPOAX) and Vanguard PRIMECAP Fund Investor Shares (VPMCX). 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.

	CPOAX	VPMCX	Difference
Sharpe ratio Return per unit of total volatility	0.49	3.75	-3.25
Sortino ratio Return per unit of downside risk	0.86	5.04	-4.18
Omega ratio Gain probability vs. loss probability	1.10	1.65	-0.55
Calmar ratio Return relative to maximum drawdown	0.50	5.12	-4.62
Martin ratio Return relative to average drawdown	1.08	23.59	-22.52
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

CPOAX vs. VPMCX - Sharpe Ratio Comparison

The current CPOAX Sharpe Ratio is 0.49, which is lower than the VPMCX Sharpe Ratio of 3.75. The chart below compares the historical Sharpe Ratios of CPOAX and VPMCX, 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

	CPOAX	VPMCX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.49	3.75	-3.25
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.01	0.91	-0.90
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.50	0.92	-0.41
Sharpe Ratio (All Time) Calculated using the full available price history	0.35	0.81	-0.46

Drawdowns

CPOAX vs. VPMCX - Drawdown Comparison

The maximum CPOAX drawdown since its inception was -84.57%, which is greater than VPMCX's maximum drawdown of -50.45%. Use the drawdown chart below to compare losses from any high point for CPOAX and VPMCX.

Drawdown Indicators

	CPOAX	VPMCX	Difference
Max Drawdown Largest peak-to-trough decline	-84.57%	-50.45%	-34.12%
Max Drawdown (1Y) Largest decline over 1 year	-28.37%	-11.73%	-16.64%
Max Drawdown (3Y) Largest decline over 3 years	-31.38%	-20.56%	-10.82%
Max Drawdown (5Y) Largest decline over 5 years	-70.73%	-25.25%	-45.48%
Max Drawdown (10Y) Largest decline over 10 years	-71.33%	-32.65%	-38.68%
Current Drawdown Current decline from peak	-17.08%	0.00%	-17.08%
Average Drawdown Average peak-to-trough decline	-39.22%	-7.41%	-31.81%
Ulcer Index Depth and duration of drawdowns from previous peaks	13.13%	2.54%	+10.59%

Volatility

CPOAX vs. VPMCX - Volatility Comparison

Morgan Stanley Insight A (CPOAX) has a higher volatility of 8.49% compared to Vanguard PRIMECAP Fund Investor Shares (VPMCX) at 6.18%. This indicates that CPOAX's price experiences larger fluctuations and is considered to be riskier than VPMCX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	CPOAX	VPMCX	Difference
Volatility (1M) Calculated over the trailing 1-month period	8.49%	6.18%	+2.31%
Volatility (6M) Calculated over the trailing 6-month period	21.71%	12.85%	+8.86%
Volatility (1Y) Calculated over the trailing 1-year period	28.66%	16.02%	+12.64%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	39.75%	18.26%	+21.49%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	34.08%	19.19%	+14.89%

CPOAX vs. VPMCX - Expense Ratio Comparison

CPOAX has a 1.15% expense ratio, which is higher than VPMCX's 0.38% expense ratio.

Dividends

CPOAX vs. VPMCX - Dividend Comparison

CPOAX has not paid dividends to shareholders, while VPMCX's dividend yield for the trailing twelve months is around 13.04%.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
CPOAX Morgan Stanley Insight A	0.00%	0.00%	0.61%	0.00%	51.84%	14.94%	9.06%	7.29%	9.33%	28.73%	9.83%	8.92%
VPMCX Vanguard PRIMECAP Fund Investor Shares	13.04%	16.36%	6.62%	7.16%	9.85%	10.08%	9.74%	7.15%	8.32%	4.53%	5.05%	5.91%

Frequently Asked Questions

Can I hold both CPOAX and VPMCX in my portfolio?

CPOAX and VPMCX have a correlation of 0.58, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, CPOAX or VPMCX?

CPOAX has higher volatility (8.49%) compared to VPMCX (6.18%). In terms of maximum drawdown, CPOAX dropped -84.57% vs VPMCX's -50.45%.

Which has better risk-adjusted returns?

VPMCX currently has the higher Sharpe Ratio (3.75 vs 0.49), 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.