PMFMX vs. PSSMX

Last updated Jun 5, 2026

PMFMX (Principal MidCap S&P 400 Index Fund) and PSSMX (Principal SmallCap S&P 600 Index Fund) are both mutual funds - PMFMX is a Mid Cap Blend Equities fund managed by Principal, while PSSMX is a Small Cap Blend Equities fund managed by Principal. Over the past 10 years, PMFMX returned 11.92%/yr vs 10.73%/yr for PSSMX. With a 0.96 correlation, they move nearly in lockstep. Both charge a 0.73% expense ratio.

Performance

PMFMX vs. PSSMX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Principal MidCap S&P 400 Index Fund (PMFMX) and Principal SmallCap S&P 600 Index Fund (PSSMX). 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 lower than PSSMX's 14.99% return. Over the past 10 years, PMFMX has outperformed PSSMX with an annualized return of 11.92%, while PSSMX has yielded a comparatively lower 10.73% annualized return.

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%

PSSMX

• 1D: -0.85%
• 1M: 0.17%
• YTD: 14.99%
• 6M: 13.97%
• 1Y: 31.04%
• 3Y*: 16.63%
• 5Y*: 6.58%
• 10Y*: 10.73%

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

PMFMX vs. PSSMX - 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%
PSSMX Principal SmallCap S&P 600 Index Fund	14.99%	5.34%	16.60%	15.18%	-16.69%	25.39%	10.65%	21.99%	-9.42%	12.46%

Correlation

The correlation between PMFMX and PSSMX is 0.94, 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	0.94
Correlation (3Y) Calculated over the trailing 3-year period	0.95
Correlation (5Y) Calculated over the trailing 5-year period	0.96
Correlation (10Y) Calculated over the trailing 10-year period	0.96
Correlation (All Time) Calculated using the full available price history since Jan 3, 2001	0.96

The correlation between PMFMX and PSSMX has been stable across timeframes, ranging from 0.94 to 0.96 - a consistent structural relationship.

Return for Risk

PMFMX vs. PSSMX — 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

PSSMX

PSSMX Risk / Return Rank: 50
PSSMX Sharpe Ratio Rank: 38
PSSMX Sortino Ratio Rank: 39
PSSMX Omega Ratio Rank: 35
PSSMX Calmar Ratio Rank: 79
PSSMX Martin Ratio Rank: 60

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. PSSMX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Principal MidCap S&P 400 Index Fund (PMFMX) and Principal SmallCap S&P 600 Index Fund (PSSMX). 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	PSSMX	Difference
Sharpe ratio: Return per unit of total volatility	1.61	1.77	-0.16
Sortino ratio: Return per unit of downside risk	2.37	2.60	-0.23
Omega ratio: Gain probability vs. loss probability	1.29	1.31	-0.02
Calmar ratio: Return relative to maximum drawdown	2.78	3.52	-0.74
Martin ratio: Return relative to average drawdown	10.13	11.76	-1.63
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. PSSMX - Sharpe Ratio Comparison

The current PMFMX Sharpe Ratio is 1.61, which is comparable to the PSSMX Sharpe Ratio of 1.77. The chart below compares the historical Sharpe Ratios of PMFMX and PSSMX, 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	PSSMX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.61	1.77	-0.16
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.50	0.30	+0.20
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.57	0.47	+0.10
Sharpe Ratio (All Time) Calculated using the full available price history	0.44	0.41	+0.03

Drawdowns

PMFMX vs. PSSMX - Drawdown Comparison

The maximum PMFMX drawdown since its inception was -55.43%, smaller than the maximum PSSMX drawdown of -58.43%. Use the drawdown chart below to compare losses from any high point for PMFMX and PSSMX.

Drawdown Indicators

	PMFMX	PSSMX	Difference
Max Drawdown Largest peak-to-trough decline	-55.43%	-58.43%	+3.00%
Max Drawdown (1Y) Largest decline over 1 year	-8.89%	-8.76%	-0.13%
Max Drawdown (3Y) Largest decline over 3 years	-22.09%	-24.30%	+2.21%
Max Drawdown (5Y) Largest decline over 5 years	-24.08%	-27.01%	+2.93%
Max Drawdown (10Y) Largest decline over 10 years	-42.02%	-44.85%	+2.83%
Current Drawdown Current decline from peak	-0.12%	-0.91%	+0.79%
Average Drawdown Average peak-to-trough decline	-7.81%	-9.52%	+1.71%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.44%	2.62%	-0.18%

Volatility

PMFMX vs. PSSMX - Volatility Comparison

Principal MidCap S&P 400 Index Fund (PMFMX) and Principal SmallCap S&P 600 Index Fund (PSSMX) have volatilities of 4.38% and 4.43%, 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

	PMFMX	PSSMX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.38%	4.43%	-0.05%
Volatility (6M) Calculated over the trailing 6-month period	11.29%	11.71%	-0.42%
Volatility (1Y) Calculated over the trailing 1-year period	15.37%	17.48%	-2.11%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	20.57%	21.76%	-1.19%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	21.00%	22.91%	-1.91%

PMFMX vs. PSSMX - Expense Ratio Comparison

Both PMFMX and PSSMX have an expense ratio of 0.73%.

Dividends

PMFMX vs. PSSMX - Dividend Comparison

PMFMX's dividend yield for the trailing twelve months is around 7.21%, less than PSSMX's 8.68% 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%
PSSMX Principal SmallCap S&P 600 Index Fund	8.68%	9.98%	15.91%	3.75%	10.45%	8.23%	1.67%	6.56%	13.08%	6.03%	6.15%	8.07%

Frequently Asked Questions

Can I hold both PMFMX and PSSMX in my portfolio?

With a correlation of 0.94, PMFMX and PSSMX 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 PSSMX?

PSSMX has higher volatility (4.43%) compared to PMFMX (4.38%). In terms of maximum drawdown, PMFMX dropped -55.43% vs PSSMX's -58.43%.

Which has better risk-adjusted returns?

PSSMX currently has the higher Sharpe Ratio (1.77 vs 1.61), 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.