VSMPX vs. PRBLX

Last updated Jul 15, 2026

VSMPX (Vanguard Total Stock Market Index Fund Institutional Plus Shares) and PRBLX (Parnassus Core Equity Fund Investor Shares) are both Large Cap Blend Equities funds. VSMPX is passively managed, while PRBLX is actively managed. Over the past 10 years, VSMPX returned 14.67%/yr vs 13.51%/yr for PRBLX. Their correlation of 0.94 suggests significant overlap in exposure. VSMPX charges 0.02%/yr vs 0.81%/yr for PRBLX.

Performance

VSMPX vs. PRBLX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard Total Stock Market Index Fund Institutional Plus Shares (VSMPX) and Parnassus Core Equity Fund Investor Shares (PRBLX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, VSMPX achieves a 10.95% return, which is significantly higher than PRBLX's 8.52% return. Over the past 10 years, VSMPX has outperformed PRBLX with an annualized return of 14.67%, while PRBLX has yielded a comparatively lower 13.51% annualized return.

VSMPX

• 1D: -0.79%
• 1M: 1.18%
• 6M: 8.63%
• YTD: 10.95%
• 1Y: 21.55%
• 3Y*: 19.79%
• 5Y*: 12.03%
• 10Y*: 14.67%

PRBLX

• 1D: -0.64%
• 1M: 2.05%
• 6M: 5.77%
• YTD: 8.52%
• 1Y: 12.18%
• 3Y*: 15.33%
• 5Y*: 9.85%
• 10Y*: 13.51%

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

VSMPX vs. PRBLX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
VSMPX Vanguard Total Stock Market Index Fund Institutional Plus Shares	10.95%	17.15%	23.26%	26.53%	-19.50%	25.74%	21.01%	30.79%	-5.16%	21.19%
PRBLX Parnassus Core Equity Fund Investor Shares	8.52%	11.67%	18.58%	24.97%	-18.64%	27.59%	21.21%	30.68%	-0.30%	16.63%

Correlation

The correlation between VSMPX and PRBLX is 0.92, 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	0.92
Correlation (3Y) Calculated over the trailing 3-year period	0.93
Correlation (5Y) Calculated over the trailing 5-year period	0.95
Correlation (10Y) Calculated over the trailing 10-year period	0.94
Correlation (All Time) Calculated using the full available price history since Jan 4, 2016	0.94

The correlation between VSMPX and PRBLX has been stable across timeframes, ranging from 0.92 to 0.95 - a consistent structural relationship.

Return for Risk

VSMPX vs. PRBLX — Risk / Return Rank

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

VSMPX

VSMPX Risk / Return Rank: 62
VSMPX Sharpe Ratio Rank: 59
VSMPX Sortino Ratio Rank: 55
VSMPX Omega Ratio Rank: 55
VSMPX Calmar Ratio Rank: 65
VSMPX Martin Ratio Rank: 75

PRBLX

PRBLX Risk / Return Rank: 21
PRBLX Sharpe Ratio Rank: 22
PRBLX Sortino Ratio Rank: 22
PRBLX Omega Ratio Rank: 21
PRBLX Calmar Ratio Rank: 17
PRBLX Martin Ratio Rank: 23

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.

VSMPX vs. PRBLX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard Total Stock Market Index Fund Institutional Plus Shares (VSMPX) and Parnassus Core Equity Fund Investor Shares (PRBLX). 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.

	VSMPX	PRBLX	Difference
Sharpe ratio: Return per unit of total volatility	1.71	0.99	+0.71
Sortino ratio: Return per unit of downside risk	2.36	1.45	+0.91
Omega ratio: Gain probability vs. loss probability	1.31	1.18	+0.13
Calmar ratio: Return relative to maximum drawdown	2.46	1.07	+1.39
Martin ratio: Return relative to average drawdown	10.80	4.14	+6.65

VSMPX vs. PRBLX - Sharpe Ratio Comparison

The current VSMPX Sharpe Ratio is 1.71, which is higher than the PRBLX Sharpe Ratio of 0.99. The chart below compares the historical Sharpe Ratios of VSMPX and PRBLX, 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

VSMPX vs. PRBLX - Drawdown Comparison

The maximum VSMPX drawdown since its inception was -34.97%, smaller than the maximum PRBLX drawdown of -42.20%. Use the drawdown chart below to compare losses from any high point for VSMPX and PRBLX.

Drawdown Indicators

	VSMPX	PRBLX	Difference
Max Drawdown Largest peak-to-trough decline	-34.97%	-42.20%	+7.23%
Max Drawdown (1Y) Largest decline over 1 year	-8.92%	-11.63%	+2.71%
Max Drawdown (3Y) Largest decline over 3 years	-19.36%	-16.31%	-3.05%
Max Drawdown (5Y) Largest decline over 5 years	-25.35%	-26.31%	+0.96%
Max Drawdown (10Y) Largest decline over 10 years	-34.97%	-30.09%	-4.88%
Current Drawdown Current decline from peak	-0.93%	-1.01%	+0.08%
Average Drawdown Average peak-to-trough decline	-4.56%	-4.04%	-0.52%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.03%	2.99%	-0.96%

Volatility

VSMPX vs. PRBLX - Volatility Comparison

The current volatility for Vanguard Total Stock Market Index Fund Institutional Plus Shares (VSMPX) is 3.99%, while Parnassus Core Equity Fund Investor Shares (PRBLX) has a volatility of 4.45%. This indicates that VSMPX experiences smaller price fluctuations and is considered to be less risky than PRBLX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VSMPX	PRBLX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.99%	4.45%	-0.46%
Volatility (6M) Calculated over the trailing 6-month period	10.17%	10.24%	-0.07%
Volatility (1Y) Calculated over the trailing 1-year period	12.88%	12.59%	+0.29%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.46%	16.38%	+1.08%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.39%	17.26%	+1.13%

VSMPX vs. PRBLX - Expense Ratio Comparison

VSMPX has a 0.02% expense ratio, which is lower than PRBLX's 0.81% expense ratio.

Dividends

VSMPX vs. PRBLX - Dividend Comparison

VSMPX's dividend yield for the trailing twelve months is around 1.06%, less than PRBLX's 17.54% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
PRBLX Parnassus Core Equity Fund Investor Shares	17.54%	19.08%	10.00%	6.01%	10.13%	7.77%	5.87%	8.02%	9.64%	7.16%	3.80%	9.62%
VSMPX Vanguard Total Stock Market Index Fund Institutional Plus Shares	1.06%	1.13%	1.27%	1.43%	1.67%	1.22%	1.43%	1.78%	2.05%	1.73%	1.95%	0.00%

Frequently Asked Questions

Can I hold both VSMPX and PRBLX in my portfolio?

With a correlation of 0.92, VSMPX and PRBLX 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, VSMPX or PRBLX?

PRBLX has higher volatility (4.45%) compared to VSMPX (3.99%). In terms of maximum drawdown, VSMPX dropped -34.97% vs PRBLX's -42.20%.

Which has better risk-adjusted returns?

VSMPX currently has the higher Sharpe Ratio (1.71 vs 0.99), 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.