THPMX vs. FSMDX

Last updated Jun 24, 2026

THPMX (Thompson MidCap Fund) and FSMDX (Fidelity Mid Cap Index Fund) are both Mid Cap Blend Equities funds. Over the past 10 years, THPMX returned 11.68%/yr vs 12.12%/yr for FSMDX. Their correlation of 0.93 suggests significant overlap in exposure. THPMX charges 1.15%/yr vs 0.03%/yr for FSMDX.

Performance

THPMX vs. FSMDX - Performance Comparison

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

Returns By Period

In the year-to-date period, THPMX achieves a 12.42% return, which is significantly lower than FSMDX's 14.03% return. Both investments have delivered pretty close results over the past 10 years, with THPMX having a 11.68% annualized return and FSMDX not far ahead at 12.12%.

THPMX

• 1D: -0.12%
• 1M: 2.29%
• YTD: 12.42%
• 6M: 11.67%
• 1Y: 32.92%
• 3Y*: 17.15%
• 5Y*: 8.38%
• 10Y*: 11.68%

FSMDX

• 1D: 0.53%
• 1M: 3.31%
• YTD: 14.03%
• 6M: 12.50%
• 1Y: 22.60%
• 3Y*: 17.64%
• 5Y*: 8.51%
• 10Y*: 12.12%

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

THPMX vs. FSMDX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
THPMX Thompson MidCap Fund	12.42%	20.08%	7.70%	17.01%	-14.84%	29.71%	11.97%	33.48%	-21.90%	17.10%
FSMDX Fidelity Mid Cap Index Fund	14.03%	10.58%	15.55%	17.20%	-17.27%	22.56%	17.13%	30.53%	-9.38%	18.04%

Correlation

The correlation between THPMX and FSMDX 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	0.92
Correlation (5Y) Calculated over the trailing 5-year period	0.94
Correlation (10Y) Calculated over the trailing 10-year period	0.92
Correlation (All Time) Calculated using the full available price history since Sep 9, 2011	0.93

The correlation between THPMX and FSMDX has been stable across timeframes, ranging from 0.91 to 0.94 - a consistent structural relationship.

Return for Risk

THPMX vs. FSMDX — Risk / Return Rank

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

THPMX

THPMX Risk / Return Rank: 69
THPMX Sharpe Ratio Rank: 68
THPMX Sortino Ratio Rank: 68
THPMX Omega Ratio Rank: 58
THPMX Calmar Ratio Rank: 80
THPMX Martin Ratio Rank: 69

FSMDX

FSMDX Risk / Return Rank: 48
FSMDX Sharpe Ratio Rank: 41
FSMDX Sortino Ratio Rank: 40
FSMDX Omega Ratio Rank: 36
FSMDX Calmar Ratio Rank: 63
FSMDX Martin Ratio Rank: 59

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.

THPMX vs. FSMDX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Thompson MidCap Fund (THPMX) and Fidelity Mid Cap Index Fund (FSMDX). 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.

	THPMX	FSMDX	Difference
Sharpe ratio: Return per unit of total volatility	2.23	1.72	+0.51
Sortino ratio: Return per unit of downside risk	3.14	2.45	+0.69
Omega ratio: Gain probability vs. loss probability	1.39	1.30	+0.09
Calmar ratio: Return relative to maximum drawdown	3.47	2.90	+0.57
Martin ratio: Return relative to average drawdown	12.46	11.11	+1.35

THPMX vs. FSMDX - Sharpe Ratio Comparison

The current THPMX Sharpe Ratio is 2.23, which is comparable to the FSMDX Sharpe Ratio of 1.72. The chart below compares the historical Sharpe Ratios of THPMX and FSMDX, 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

THPMX vs. FSMDX - Drawdown Comparison

The maximum THPMX drawdown since its inception was -47.55%, which is greater than FSMDX's maximum drawdown of -40.35%. Use the drawdown chart below to compare losses from any high point for THPMX and FSMDX.

Drawdown Indicators

	THPMX	FSMDX	Difference
Max Drawdown Largest peak-to-trough decline	-47.55%	-40.35%	-7.20%
Max Drawdown (1Y) Largest decline over 1 year	-9.90%	-8.16%	-1.74%
Max Drawdown (3Y) Largest decline over 3 years	-21.52%	-20.92%	-0.60%
Max Drawdown (5Y) Largest decline over 5 years	-25.29%	-26.07%	+0.78%
Max Drawdown (10Y) Largest decline over 10 years	-47.55%	-40.35%	-7.20%
Current Drawdown Current decline from peak	-1.55%	-0.26%	-1.29%
Average Drawdown Average peak-to-trough decline	-6.75%	-4.94%	-1.81%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.75%	2.13%	+0.62%

Volatility

THPMX vs. FSMDX - Volatility Comparison

Thompson MidCap Fund (THPMX) and Fidelity Mid Cap Index Fund (FSMDX) have volatilities of 4.42% 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

	THPMX	FSMDX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.42%	4.43%	-0.01%
Volatility (6M) Calculated over the trailing 6-month period	11.25%	10.46%	+0.79%
Volatility (1Y) Calculated over the trailing 1-year period	15.46%	13.85%	+1.61%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	20.59%	18.32%	+2.27%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	22.78%	19.35%	+3.43%

THPMX vs. FSMDX - Expense Ratio Comparison

THPMX has a 1.15% expense ratio, which is higher than FSMDX's 0.03% expense ratio.

Dividends

THPMX vs. FSMDX - Dividend Comparison

THPMX's dividend yield for the trailing twelve months is around 8.44%, more than FSMDX's 0.97% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FSMDX Fidelity Mid Cap Index Fund	0.97%	1.10%	2.46%	1.39%	2.07%	3.35%	2.34%	2.86%	2.21%	2.17%	2.23%	2.84%
THPMX Thompson MidCap Fund	8.44%	9.48%	8.04%	7.60%	12.04%	9.76%	0.33%	2.93%	7.29%	7.51%	4.84%	9.46%

Frequently Asked Questions

Can I hold both THPMX and FSMDX in my portfolio?

With a correlation of 0.91, THPMX and FSMDX 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, THPMX or FSMDX?

FSMDX has higher volatility (4.43%) compared to THPMX (4.42%). In terms of maximum drawdown, THPMX dropped -47.55% vs FSMDX's -40.35%.

Which has better risk-adjusted returns?

THPMX currently has the higher Sharpe Ratio (2.23 vs 1.72), 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.