SPY vs. TDG

Last updated Jun 9, 2026

SPY (State Street SPDR S&P 500 ETF) is S&P 500 fund tracking the S&P 500 Index, while TDG (TransDigm Group Incorporated) is a stock. Over the past 10 years, SPY returned 15.27%/yr vs 22.15%/yr for TDG. A 0.55 correlation means they provide meaningful diversification when combined.

Performance

SPY vs. TDG - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in State Street SPDR S&P 500 ETF (SPY) and TransDigm Group Incorporated (TDG). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, SPY achieves a 8.70% return, which is significantly higher than TDG's -9.29% return. Over the past 10 years, SPY has underperformed TDG with an annualized return of 15.27%, while TDG has yielded a comparatively higher 22.15% annualized return.

SPY

• 1D: 0.23%
• 1M: 0.22%
• YTD: 8.70%
• 6M: 8.75%
• 1Y: 24.79%
• 3Y*: 21.35%
• 5Y*: 13.42%
• 10Y*: 15.27%

TDG

• 1D: -2.62%
• 1M: -0.72%
• YTD: -9.29%
• 6M: -10.46%
• 1Y: -12.05%
• 3Y*: 20.83%
• 5Y*: 16.93%
• 10Y*: 22.15%

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

SPY vs. TDG - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
SPY State Street SPDR S&P 500 ETF	8.70%	17.72%	24.89%	26.18%	-18.18%	28.73%	18.33%	31.22%	-4.57%	21.71%
TDG TransDigm Group Incorporated	-9.29%	12.15%	32.27%	66.57%	1.77%	2.82%	10.51%	84.41%	23.83%	19.84%

Correlation

The correlation between SPY and TDG is 0.31, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.31
Correlation (3Y) Calculated over the trailing 3-year period	0.46
Correlation (5Y) Calculated over the trailing 5-year period	0.57
Correlation (10Y) Calculated over the trailing 10-year period	0.56
Correlation (All Time) Calculated using the full available price history since Mar 16, 2006	0.55

Over the past year, the correlation between SPY and TDG has dropped to 0.31 - well below their long-term average of 0.55, suggesting their price drivers have been diverging.

Return for Risk

SPY vs. TDG — Risk / Return Rank

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

SPY

SPY Risk / Return Rank: 69
SPY Sharpe Ratio Rank: 70
SPY Sortino Ratio Rank: 67
SPY Omega Ratio Rank: 70
SPY Calmar Ratio Rank: 62
SPY Martin Ratio Rank: 75

TDG

TDG Risk / Return Rank: 24
TDG Sharpe Ratio Rank: 23
TDG Sortino Ratio Rank: 22
TDG Omega Ratio Rank: 21
TDG Calmar Ratio Rank: 26
TDG Martin Ratio Rank: 26

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.

SPY vs. TDG - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for State Street SPDR S&P 500 ETF (SPY) and TransDigm Group Incorporated (TDG). 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.

	SPY	TDG	Difference
Sharpe ratio: Return per unit of total volatility	2.06	-0.44	+2.50
Sortino ratio: Return per unit of downside risk	2.78	-0.41	+3.19
Omega ratio: Gain probability vs. loss probability	1.38	0.94	+0.43
Calmar ratio: Return relative to maximum drawdown	2.80	-0.48	+3.28
Martin ratio: Return relative to average drawdown	12.93	-0.83	+13.76
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

SPY vs. TDG - Sharpe Ratio Comparison

The current SPY Sharpe Ratio is 2.06, which is higher than the TDG Sharpe Ratio of -0.44. The chart below compares the historical Sharpe Ratios of SPY and TDG, 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

	SPY	TDG	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.06	-0.44	+2.50
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.79	0.61	+0.18
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.85	0.66	+0.20
Sharpe Ratio (All Time) Calculated using the full available price history	0.58	0.85	-0.26

Drawdowns

SPY vs. TDG - Drawdown Comparison

The maximum SPY drawdown since its inception was -55.19%, smaller than the maximum TDG drawdown of -62.64%. Use the drawdown chart below to compare losses from any high point for SPY and TDG.

Drawdown Indicators

	SPY	TDG	Difference
Max Drawdown Largest peak-to-trough decline	-55.19%	-62.64%	+7.45%
Max Drawdown (1Y) Largest decline over 1 year	-8.88%	-25.30%	+16.42%
Max Drawdown (3Y) Largest decline over 3 years	-18.76%	-25.30%	+6.54%
Max Drawdown (5Y) Largest decline over 5 years	-24.50%	-25.30%	+0.80%
Max Drawdown (10Y) Largest decline over 10 years	-33.72%	-62.64%	+28.92%
Current Drawdown Current decline from peak	-2.68%	-20.46%	+17.78%
Average Drawdown Average peak-to-trough decline	-9.04%	-7.95%	-1.09%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.92%	14.58%	-12.66%

Volatility

SPY vs. TDG - Volatility Comparison

The current volatility for State Street SPDR S&P 500 ETF (SPY) is 3.72%, while TransDigm Group Incorporated (TDG) has a volatility of 7.72%. This indicates that SPY experiences smaller price fluctuations and is considered to be less risky than TDG based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	SPY	TDG	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.72%	7.72%	-4.00%
Volatility (6M) Calculated over the trailing 6-month period	9.31%	21.00%	-11.69%
Volatility (1Y) Calculated over the trailing 1-year period	12.10%	27.63%	-15.53%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.09%	27.81%	-10.72%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	17.96%	33.78%	-15.82%

Dividends

SPY vs. TDG - Dividend Comparison

SPY's dividend yield for the trailing twelve months is around 1.00%, less than TDG's 7.46% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
SPY State Street SPDR S&P 500 ETF	1.00%	1.07%	1.21%	1.40%	1.65%	1.20%	1.52%	1.75%	2.04%	1.80%	2.03%	2.06%
TDG TransDigm Group Incorporated	7.46%	6.77%	5.92%	3.46%	2.94%	0.00%	0.00%	11.16%	0.00%	8.01%	9.64%	0.00%

Frequently Asked Questions

Can I hold both SPY and TDG in my portfolio?

SPY and TDG have a correlation of 0.31, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, SPY or TDG?

TDG has higher volatility (7.72%) compared to SPY (3.72%). In terms of maximum drawdown, SPY dropped -55.19% vs TDG's -62.64%.

Which has better risk-adjusted returns?

SPY currently has the higher Sharpe Ratio (2.06 vs -0.44), 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.