PTDIX vs. FXAIX

Last updated Jun 23, 2026

PTDIX (Principal LifeTime 2040 Fund) and FXAIX (Fidelity 500 Index Fund) are both mutual funds - PTDIX is a Target Retirement Date fund managed by Principal, while FXAIX is a S&P 500 fund tracking the S&P 500 Index. Over the past 10 years, PTDIX returned 10.60%/yr vs 15.58%/yr for FXAIX. With a 0.95 correlation, they move nearly in lockstep. PTDIX charges 0.01%/yr vs 0.02%/yr for FXAIX.

Performance

PTDIX vs. FXAIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Principal LifeTime 2040 Fund (PTDIX) and Fidelity 500 Index Fund (FXAIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, PTDIX achieves a 7.32% return, which is significantly lower than FXAIX's 10.19% return. Over the past 10 years, PTDIX has underperformed FXAIX with an annualized return of 10.60%, while FXAIX has yielded a comparatively higher 15.58% annualized return.

PTDIX

• 1D: 1.02%
• 1M: 1.53%
• YTD: 7.32%
• 6M: 7.21%
• 1Y: 18.66%
• 3Y*: 16.00%
• 5Y*: 8.36%
• 10Y*: 10.60%

FXAIX

• 1D: 1.09%
• 1M: 0.47%
• YTD: 10.19%
• 6M: 9.68%
• 1Y: 27.18%
• 3Y*: 20.98%
• 5Y*: 14.10%
• 10Y*: 15.58%

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

PTDIX vs. FXAIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
PTDIX Principal LifeTime 2040 Fund	7.32%	15.59%	17.43%	18.33%	-18.13%	15.35%	16.04%	24.91%	-7.95%	20.69%
FXAIX Fidelity 500 Index Fund	10.19%	17.84%	25.01%	26.29%	-18.14%	28.71%	18.42%	31.48%	-4.43%	21.82%

Correlation

The correlation between PTDIX and FXAIX is 0.93, 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	0.93
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	0.94
Correlation (All Time) Calculated using the full available price history since May 4, 2011	0.95

The correlation between PTDIX and FXAIX has been stable across timeframes, ranging from 0.92 to 0.95 - a consistent structural relationship.

Return for Risk

PTDIX vs. FXAIX — Risk / Return Rank

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

PTDIX

PTDIX Risk / Return Rank: 47
PTDIX Sharpe Ratio Rank: 42
PTDIX Sortino Ratio Rank: 41
PTDIX Omega Ratio Rank: 43
PTDIX Calmar Ratio Rank: 48
PTDIX Martin Ratio Rank: 58

FXAIX

FXAIX Risk / Return Rank: 66
FXAIX Sharpe Ratio Rank: 64
FXAIX Sortino Ratio Rank: 59
FXAIX Omega Ratio Rank: 61
FXAIX Calmar Ratio Rank: 68
FXAIX Martin Ratio Rank: 79

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.

PTDIX vs. FXAIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Principal LifeTime 2040 Fund (PTDIX) and Fidelity 500 Index Fund (FXAIX). 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.

	PTDIX	FXAIX	Difference
Sharpe ratio: Return per unit of total volatility	1.78	2.17	-0.39
Sortino ratio: Return per unit of downside risk	2.51	2.93	-0.42
Omega ratio: Gain probability vs. loss probability	1.33	1.39	-0.06
Calmar ratio: Return relative to maximum drawdown	2.52	3.04	-0.52
Martin ratio: Return relative to average drawdown	10.99	13.75	-2.76

PTDIX vs. FXAIX - Sharpe Ratio Comparison

The current PTDIX Sharpe Ratio is 1.78, which is comparable to the FXAIX Sharpe Ratio of 2.17. The chart below compares the historical Sharpe Ratios of PTDIX and FXAIX, 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

PTDIX vs. FXAIX - Drawdown Comparison

The maximum PTDIX drawdown since its inception was -54.38%, which is greater than FXAIX's maximum drawdown of -33.79%. Use the drawdown chart below to compare losses from any high point for PTDIX and FXAIX.

Drawdown Indicators

	PTDIX	FXAIX	Difference
Max Drawdown Largest peak-to-trough decline	-54.38%	-33.79%	-20.59%
Max Drawdown (1Y) Largest decline over 1 year	-7.32%	-8.89%	+1.57%
Max Drawdown (3Y) Largest decline over 3 years	-13.05%	-18.76%	+5.71%
Max Drawdown (5Y) Largest decline over 5 years	-25.43%	-24.50%	-0.93%
Max Drawdown (10Y) Largest decline over 10 years	-30.02%	-33.79%	+3.77%
Current Drawdown Current decline from peak	-0.45%	-1.36%	+0.91%
Average Drawdown Average peak-to-trough decline	-7.48%	-3.79%	-3.69%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.68%	1.96%	-0.28%

Volatility

PTDIX vs. FXAIX - Volatility Comparison

The current volatility for Principal LifeTime 2040 Fund (PTDIX) is 4.05%, while Fidelity 500 Index Fund (FXAIX) has a volatility of 4.77%. This indicates that PTDIX experiences smaller price fluctuations and is considered to be less risky than FXAIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	PTDIX	FXAIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.05%	4.77%	-0.72%
Volatility (6M) Calculated over the trailing 6-month period	8.56%	9.91%	-1.35%
Volatility (1Y) Calculated over the trailing 1-year period	10.36%	12.47%	-2.11%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	13.58%	17.01%	-3.43%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	13.86%	18.11%	-4.25%

PTDIX vs. FXAIX - Expense Ratio Comparison

PTDIX has a 0.01% expense ratio, which is lower than FXAIX's 0.02% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

PTDIX vs. FXAIX - Dividend Comparison

PTDIX's dividend yield for the trailing twelve months is around 9.13%, more than FXAIX's 1.04% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FXAIX Fidelity 500 Index Fund	1.04%	1.11%	1.25%	1.45%	1.69%	1.22%	1.60%	2.06%	2.72%	1.97%	2.52%	2.83%
PTDIX Principal LifeTime 2040 Fund	9.13%	9.80%	12.28%	4.40%	8.61%	8.92%	6.01%	7.26%	9.28%	6.07%	4.86%	6.73%

Frequently Asked Questions

Can I hold both PTDIX and FXAIX in my portfolio?

With a correlation of 0.93, PTDIX and FXAIX 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, PTDIX or FXAIX?

FXAIX has higher volatility (4.77%) compared to PTDIX (4.05%). In terms of maximum drawdown, PTDIX dropped -54.38% vs FXAIX's -33.79%.

Which has better risk-adjusted returns?

FXAIX currently has the higher Sharpe Ratio (2.17 vs 1.78), 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.