PEXMX vs. PRDMX
PEXMX (T. Rowe Price Extended Equity Market Index Fund) and PRDMX (T. Rowe Price Diversified Mid Cap Growth Fund) are both Mid Cap Growth Equities funds from T. Rowe Price. Over the past 10 years, PEXMX returned 11.71%/yr vs 12.24%/yr for PRDMX. Their correlation of 0.94 means they have usually moved in the same direction. PEXMX charges 0.23%/yr vs 0.79%/yr for PRDMX.
Performance
PEXMX vs. PRDMX - Performance Comparison
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Returns By Period
In the year-to-date period, PEXMX achieves a 13.95% return, which is significantly higher than PRDMX's 1.86% return. Both investments have delivered pretty close results over the past 10 years, with PEXMX having a 11.71% annualized return and PRDMX not far ahead at 12.24%.
PEXMX
- 1D
- 1.40%
- 1M
- -2.42%
- 6M
- 9.57%
- YTD
- 13.95%
- 1Y
- 23.74%
- 3Y*
- 15.83%
- 5Y*
- 6.13%
- 10Y*
- 11.71%
- ALL TIME*
- 9.07%
PRDMX
- 1D
- 2.48%
- 1M
- -3.51%
- 6M
- 2.10%
- YTD
- 1.86%
- 1Y
- 0.92%
- 3Y*
- 12.67%
- 5Y*
- 5.14%
- 10Y*
- 12.24%
- ALL TIME*
- 10.44%
Liquidity Comparison
| Position | Avg. Volume Value (2W) | Avg. Volume Value (1M) | Avg. Volume Value (3M) |
|---|---|---|---|
| $0.00 | $0.00 | $0.00 | |
| $0.00 | $0.00 | $0.00 |
PEXMX vs. PRDMX - Yearly Performance Comparison
| 2026 (YTD) | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|---|
PEXMX T. Rowe Price Extended Equity Market Index Fund | 13.95% | 11.17% | 16.72% | 25.32% | -26.15% | 12.09% | 30.80% | 32.57% | -9.61% | 16.63% |
PRDMX T. Rowe Price Diversified Mid Cap Growth Fund | 1.86% | 10.30% | 23.77% | 20.75% | -24.65% | 13.56% | 31.82% | 37.91% | -3.15% | 24.66% |
Correlation
The correlation between PEXMX and PRDMX is 0.91, meaning they have usually moved in the same direction, including during past declines.
| Correlation | |
|---|---|
Correlation (1Y) Focuses on recent behavior, but can change the most. | 0.91 |
Correlation (3Y) Balances recent behavior with more history. | 0.90 |
Correlation (5Y) Shows whether the relationship held over a longer period. | 0.93 |
Correlation (10Y) Provides a long-term view across more market conditions. | 0.91 |
Correlation (All Time) Calculated using the full available price history since Jan 2, 2004 | 0.94 |
The correlation between PEXMX and PRDMX has been stable across timeframes, ranging from 0.90 to 0.94 - a consistent structural relationship.
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Return for Risk
PEXMX vs. PRDMX — Risk / Return Rank
PEXMX
PRDMX
PEXMX vs. PRDMX - Risk-Adjusted Trends Comparison
This table presents a comparison of risk-adjusted performance metrics for T. Rowe Price Extended Equity Market Index Fund (PEXMX) and T. Rowe Price Diversified Mid Cap Growth Fund (PRDMX). 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.
| PEXMX | PRDMX | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | +1.22 | ||
| Sortino ratioReturn per unit of downside risk | +1.70 | ||
| Omega ratioGain probability vs. loss probability | 1.21 | 1.01 | +0.20 |
| Calmar ratioReturn relative to maximum drawdown | 2.06 | -0.07 | +2.13 |
| Martin ratioReturn relative to average drawdown | 7.00 | -0.20 | +7.20 |
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Drawdowns
PEXMX vs. PRDMX - Drawdown Comparison
The maximum PEXMX drawdown since its inception was -57.82%, roughly equal to the maximum PRDMX drawdown of -57.57%. Use the drawdown chart below to compare losses from any high point for PEXMX and PRDMX.
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Drawdown Indicators
| PEXMX | PRDMX | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -57.82% | -57.57% | -0.25% |
Max Drawdown (1Y)Largest decline over 1 year | -10.30% | -14.15% | +3.85% |
Max Drawdown (3Y)Largest decline over 3 years | -27.01% | -25.06% | -1.95% |
Max Drawdown (5Y)Largest decline over 5 years | -36.27% | -35.69% | -0.58% |
Max Drawdown (10Y)Largest decline over 10 years | -41.27% | -35.91% | -5.36% |
Current DrawdownCurrent decline from peak | -3.55% | -5.85% | +2.30% |
Average DrawdownAverage peak-to-trough decline | -13.55% | -8.40% | -5.15% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 3.01% | 4.74% | -1.73% |
Volatility
PEXMX vs. PRDMX - Volatility Comparison
The current volatility for T. Rowe Price Extended Equity Market Index Fund (PEXMX) is 3.86%, while T. Rowe Price Diversified Mid Cap Growth Fund (PRDMX) has a volatility of 5.24%. This indicates that PEXMX experiences smaller price fluctuations and is considered to be less risky than PRDMX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.
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Volatility by Period
| PEXMX | PRDMX | Difference | |
|---|---|---|---|
Volatility (1M)Calculated over the trailing 1-month period | 3.86% | 5.24% | -1.38% |
Volatility (6M)Calculated over the trailing 6-month period | 13.36% | 14.47% | -1.11% |
Volatility (1Y)Calculated over the trailing 1-year period | 18.10% | 18.04% | +0.06% |
Volatility (5Y)Calculated over the trailing 5-year period, annualized | 22.52% | 22.01% | +0.51% |
Volatility (10Y)Calculated over the trailing 10-year period, annualized | 22.22% | 21.40% | +0.82% |
PEXMX vs. PRDMX - Expense Ratio Comparison
PEXMX has a 0.23% expense ratio, which is lower than PRDMX's 0.79% expense ratio.
Dividends
PEXMX vs. PRDMX - Dividend Comparison
PEXMX's dividend yield for the trailing twelve months is around 3.53%, less than PRDMX's 7.60% yield.
| Position | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
PEXMX T. Rowe Price Extended Equity Market Index Fund | 3.53% | 4.02% | 7.64% | 3.64% | 7.53% | 14.87% | 2.99% | 8.17% | 6.67% | 4.50% | 5.90% | 4.81% |
PRDMX T. Rowe Price Diversified Mid Cap Growth Fund | 7.60% | 7.75% | 8.59% | 6.83% | 1.22% | 10.13% | 4.80% | 2.02% | 5.23% | 3.71% | 1.23% | 3.78% |
Frequently Asked Questions
With a correlation of 0.91, PEXMX and PRDMX 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.
PRDMX has higher volatility (5.24%) compared to PEXMX (3.86%). In terms of maximum drawdown, PEXMX dropped -57.82% vs PRDMX's -57.57%.
PEXMX currently has the higher Sharpe Ratio (1.17 vs -0.05), 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.
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