PMFMX vs. VMCIX

Last updated Jun 5, 2026

PMFMX (Principal MidCap S&P 400 Index Fund) and VMCIX (Vanguard Mid-Cap Index Fund Institutional Shares) are both Mid Cap Blend Equities funds. Over the past 10 years, PMFMX returned 11.92%/yr vs 11.54%/yr for VMCIX. With a 0.97 correlation, they move nearly in lockstep. PMFMX charges 0.73%/yr vs 0.04%/yr for VMCIX.

Performance

PMFMX vs. VMCIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Principal MidCap S&P 400 Index Fund (PMFMX) and Vanguard Mid-Cap Index Fund Institutional Shares (VMCIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, PMFMX achieves a 13.74% return, which is significantly higher than VMCIX's 10.02% return. Both investments have delivered pretty close results over the past 10 years, with PMFMX having a 11.92% annualized return and VMCIX not far behind at 11.54%.

PMFMX

• 1D: -0.12%
• 1M: 2.42%
• YTD: 13.74%
• 6M: 13.42%
• 1Y: 24.90%
• 3Y*: 20.35%
• 5Y*: 10.23%
• 10Y*: 11.92%

VMCIX

• 1D: -0.48%
• 1M: 2.36%
• YTD: 10.02%
• 6M: 9.44%
• 1Y: 18.53%
• 3Y*: 16.65%
• 5Y*: 7.86%
• 10Y*: 11.54%

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

PMFMX vs. VMCIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
PMFMX Principal MidCap S&P 400 Index Fund	13.74%	6.77%	28.52%	15.61%	-13.60%	23.61%	12.90%	25.34%	-11.89%	15.35%
VMCIX Vanguard Mid-Cap Index Fund Institutional Shares	10.02%	11.67%	14.68%	16.54%	-18.70%	24.53%	18.20%	31.04%	-9.25%	19.30%

Correlation

The correlation between PMFMX and VMCIX is 0.91, 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	0.91
Correlation (3Y) Calculated over the trailing 3-year period	0.93
Correlation (5Y) Calculated over the trailing 5-year period	0.94
Correlation (10Y) Calculated over the trailing 10-year period	0.93
Correlation (All Time) Calculated using the full available price history since Dec 7, 2000	0.97

The correlation between PMFMX and VMCIX has been stable across timeframes, ranging from 0.91 to 0.97 - a consistent structural relationship.

Return for Risk

PMFMX vs. VMCIX — Risk / Return Rank

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

PMFMX

PMFMX Risk / Return Rank: 41
PMFMX Sharpe Ratio Rank: 34
PMFMX Sortino Ratio Rank: 35
PMFMX Omega Ratio Rank: 32
PMFMX Calmar Ratio Rank: 55
PMFMX Martin Ratio Rank: 51

VMCIX

VMCIX Risk / Return Rank: 30
VMCIX Sharpe Ratio Rank: 26
VMCIX Sortino Ratio Rank: 26
VMCIX Omega Ratio Rank: 24
VMCIX Calmar Ratio Rank: 35
VMCIX Martin Ratio Rank: 39

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.

PMFMX vs. VMCIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Principal MidCap S&P 400 Index Fund (PMFMX) and Vanguard Mid-Cap Index Fund Institutional Shares (VMCIX). 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.

	PMFMX	VMCIX	Difference
Sharpe ratio: Return per unit of total volatility	1.61	1.49	+0.13
Sortino ratio: Return per unit of downside risk	2.37	2.14	+0.24
Omega ratio: Gain probability vs. loss probability	1.29	1.26	+0.03
Calmar ratio: Return relative to maximum drawdown	2.78	2.25	+0.54
Martin ratio: Return relative to average drawdown	10.13	8.53	+1.60
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

PMFMX vs. VMCIX - Sharpe Ratio Comparison

The current PMFMX Sharpe Ratio is 1.61, which is comparable to the VMCIX Sharpe Ratio of 1.49. The chart below compares the historical Sharpe Ratios of PMFMX and VMCIX, 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

	PMFMX	VMCIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.61	1.49	+0.13
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.50	0.45	+0.05
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.57	0.61	-0.04
Sharpe Ratio (All Time) Calculated using the full available price history	0.44	0.49	-0.05

Drawdowns

PMFMX vs. VMCIX - Drawdown Comparison

The maximum PMFMX drawdown since its inception was -55.43%, smaller than the maximum VMCIX drawdown of -58.86%. Use the drawdown chart below to compare losses from any high point for PMFMX and VMCIX.

Drawdown Indicators

	PMFMX	VMCIX	Difference
Max Drawdown Largest peak-to-trough decline	-55.43%	-58.86%	+3.43%
Max Drawdown (1Y) Largest decline over 1 year	-8.89%	-8.13%	-0.76%
Max Drawdown (3Y) Largest decline over 3 years	-22.09%	-18.93%	-3.16%
Max Drawdown (5Y) Largest decline over 5 years	-24.08%	-27.54%	+3.46%
Max Drawdown (10Y) Largest decline over 10 years	-42.02%	-39.30%	-2.72%
Current Drawdown Current decline from peak	-0.12%	-0.48%	+0.36%
Average Drawdown Average peak-to-trough decline	-7.81%	-7.97%	+0.16%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.44%	2.14%	+0.30%

Volatility

PMFMX vs. VMCIX - Volatility Comparison

Principal MidCap S&P 400 Index Fund (PMFMX) has a higher volatility of 4.38% compared to Vanguard Mid-Cap Index Fund Institutional Shares (VMCIX) at 3.02%. This indicates that PMFMX's price experiences larger fluctuations and is considered to be riskier than VMCIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	PMFMX	VMCIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.38%	3.02%	+1.36%
Volatility (6M) Calculated over the trailing 6-month period	11.29%	9.27%	+2.02%
Volatility (1Y) Calculated over the trailing 1-year period	15.37%	12.32%	+3.05%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	20.57%	17.63%	+2.94%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	21.00%	18.92%	+2.08%

PMFMX vs. VMCIX - Expense Ratio Comparison

PMFMX has a 0.73% expense ratio, which is higher than VMCIX's 0.04% expense ratio.

Dividends

PMFMX vs. VMCIX - Dividend Comparison

PMFMX's dividend yield for the trailing twelve months is around 7.21%, more than VMCIX's 1.36% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
PMFMX Principal MidCap S&P 400 Index Fund	7.21%	8.20%	25.27%	3.11%	6.69%	7.76%	6.63%	5.52%	10.65%	6.61%	5.85%	7.40%
VMCIX Vanguard Mid-Cap Index Fund Institutional Shares	1.36%	1.52%	1.49%	1.51%	1.60%	1.12%	1.45%	1.48%	1.83%	1.36%	1.46%	1.48%

Frequently Asked Questions

Can I hold both PMFMX and VMCIX in my portfolio?

With a correlation of 0.91, PMFMX and VMCIX 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, PMFMX or VMCIX?

PMFMX has higher volatility (4.38%) compared to VMCIX (3.02%). In terms of maximum drawdown, PMFMX dropped -55.43% vs VMCIX's -58.86%.

Which has better risk-adjusted returns?

PMFMX currently has the higher Sharpe Ratio (1.61 vs 1.49), 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.