FMDGX vs. PMBMX

Last updated Apr 2, 2026

Compare and contrast key facts about Fidelity Mid Cap Growth Index Fund (FMDGX) and Principal MidCap Fund (PMBMX).

FMDGX is managed by Fidelity. It was launched on Jul 11, 2019. PMBMX is managed by Principal. It was launched on Dec 6, 2000.

Performance

FMDGX vs. PMBMX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Mid Cap Growth Index Fund (FMDGX) and Principal MidCap Fund (PMBMX). The values are adjusted to include any dividend payments, if applicable.

FMDGX vs. PMBMX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019
FMDGX Fidelity Mid Cap Growth Index Fund	-6.36%	8.60%	22.03%	25.79%	-26.67%	12.67%	34.84%	4.63%
PMBMX Principal MidCap Fund	-11.17%	1.16%	23.38%	25.36%	-23.52%	24.63%	17.69%	12.53%

Returns By Period

In the year-to-date period, FMDGX achieves a -6.36% return, which is significantly higher than PMBMX's -11.17% return.

FMDGX

• 1D: 3.60%
• 1M: -6.39%
• YTD: -6.36%
• 6M: -9.60%
• 1Y: 8.49%
• 3Y*: 12.67%
• 5Y*: 4.92%
• 10Y*: —

PMBMX

• 1D: 2.16%
• 1M: -7.75%
• YTD: -11.17%
• 6M: -13.90%
• 1Y: -10.17%
• 3Y*: 9.64%
• 5Y*: 4.79%
• 10Y*: 11.26%

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

FMDGX vs. PMBMX - Expense Ratio Comparison

FMDGX has a 0.05% expense ratio, which is lower than PMBMX's 1.15% expense ratio.

PMBMX

Principal MidCap Fund

FMDGX

Fidelity Mid Cap Growth Index Fund

Return for Risk

FMDGX vs. PMBMX — Risk / Return Rank

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

FMDGX

FMDGX Risk / Return Rank: 16
FMDGX Sharpe Ratio Rank: 14
FMDGX Sortino Ratio Rank: 16
FMDGX Omega Ratio Rank: 14
FMDGX Calmar Ratio Rank: 20
FMDGX Martin Ratio Rank: 18

PMBMX

PMBMX Risk / Return Rank: 1
PMBMX Sharpe Ratio Rank: 1
PMBMX Sortino Ratio Rank: 1
PMBMX Omega Ratio Rank: 1
PMBMX Calmar Ratio Rank: 1
PMBMX Martin Ratio Rank: 1

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.

FMDGX vs. PMBMX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Mid Cap Growth Index Fund (FMDGX) and Principal MidCap Fund (PMBMX). 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.

	FMDGX	PMBMX	Difference
Sharpe ratio Return per unit of total volatility	0.41	-0.53	+0.94
Sortino ratio Return per unit of downside risk	0.76	-0.64	+1.40
Omega ratio Gain probability vs. loss probability	1.10	0.92	+0.18
Calmar ratio Return relative to maximum drawdown	0.63	-0.53	+1.16
Martin ratio Return relative to average drawdown	1.97	-1.55	+3.52
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

FMDGX vs. PMBMX - Sharpe Ratio Comparison

The current FMDGX Sharpe Ratio is 0.41, which is higher than the PMBMX Sharpe Ratio of -0.53. The chart below compares the historical Sharpe Ratios of FMDGX and PMBMX, 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

	FMDGX	PMBMX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.41	-0.53	+0.94
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.22	0.26	-0.04
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	0.59	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.38	0.56	-0.17

Correlation

The correlation between FMDGX and PMBMX is 0.86, 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

FMDGX vs. PMBMX - Dividend Comparison

FMDGX's dividend yield for the trailing twelve months is around 1.98%, less than PMBMX's 7.22% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FMDGX Fidelity Mid Cap Growth Index Fund	1.98%	1.85%	0.47%	0.63%	0.81%	6.43%	0.36%	0.29%	0.00%	0.00%	0.00%	0.00%
PMBMX Principal MidCap Fund	7.22%	6.41%	6.86%	2.68%	3.43%	8.51%	1.15%	9.00%	12.79%	3.39%	2.16%	6.38%

Drawdowns

FMDGX vs. PMBMX - Drawdown Comparison

The maximum FMDGX drawdown since its inception was -38.59%, smaller than the maximum PMBMX drawdown of -50.69%. Use the drawdown chart below to compare losses from any high point for FMDGX and PMBMX.

Drawdown Indicators

	FMDGX	PMBMX	Difference
Max Drawdown Largest peak-to-trough decline	-38.59%	-50.69%	+12.10%
Max Drawdown (1Y) Largest decline over 1 year	-14.75%	-19.53%	+4.78%
Max Drawdown (5Y) Largest decline over 5 years	-38.59%	-31.48%	-7.11%
Max Drawdown (10Y) Largest decline over 10 years	—	-40.60%	—
Current Drawdown Current decline from peak	-11.68%	-17.13%	+5.45%
Average Drawdown Average peak-to-trough decline	-11.34%	-6.67%	-4.67%
Ulcer Index Depth and duration of drawdowns from previous peaks	4.70%	6.65%	-1.95%

Volatility

FMDGX vs. PMBMX - Volatility Comparison

Fidelity Mid Cap Growth Index Fund (FMDGX) has a higher volatility of 6.94% compared to Principal MidCap Fund (PMBMX) at 5.25%. This indicates that FMDGX's price experiences larger fluctuations and is considered to be riskier than PMBMX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FMDGX	PMBMX	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.94%	5.25%	+1.69%
Volatility (6M) Calculated over the trailing 6-month period	13.16%	10.60%	+2.56%
Volatility (1Y) Calculated over the trailing 1-year period	23.17%	18.40%	+4.77%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	22.41%	18.57%	+3.84%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	24.50%	19.12%	+5.38%