TMDIX vs. MDYG

Last updated Jun 23, 2026

TMDIX (AMG TimesSquare Mid Cap Growth Fund) and MDYG (SPDR S&P 400 Mid Cap Growth ETF) are both Mid Cap Growth Equities funds. Over the past 10 years, TMDIX returned 13.33%/yr vs 12.05%/yr for MDYG. Their correlation of 0.89 suggests significant overlap in exposure. TMDIX charges 0.98%/yr vs 0.15%/yr for MDYG.

Performance

TMDIX vs. MDYG - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in AMG TimesSquare Mid Cap Growth Fund (TMDIX) and SPDR S&P 400 Mid Cap Growth ETF (MDYG). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, TMDIX achieves a 6.08% return, which is significantly lower than MDYG's 20.44% return. Over the past 10 years, TMDIX has outperformed MDYG with an annualized return of 13.33%, while MDYG has yielded a comparatively lower 12.05% annualized return.

TMDIX

• 1D: 1.77%
• 1M: 5.20%
• YTD: 6.08%
• 6M: 3.49%
• 1Y: -0.73%
• 3Y*: 8.52%
• 5Y*: 4.28%
• 10Y*: 13.33%

MDYG

• 1D: 0.58%
• 1M: 4.15%
• YTD: 20.44%
• 6M: 17.53%
• 1Y: 32.56%
• 3Y*: 18.32%
• 5Y*: 8.79%
• 10Y*: 12.05%

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

TMDIX vs. MDYG - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
TMDIX AMG TimesSquare Mid Cap Growth Fund	6.08%	-1.76%	10.84%	25.07%	-22.26%	16.75%	33.42%	63.26%	-4.28%	22.66%
MDYG SPDR S&P 400 Mid Cap Growth ETF	20.44%	7.22%	15.84%	17.30%	-18.92%	18.46%	22.57%	26.10%	-10.46%	19.61%

Correlation

The correlation between TMDIX and MDYG is 0.87, 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	0.87
Correlation (3Y) Calculated over the trailing 3-year period	0.88
Correlation (5Y) Calculated over the trailing 5-year period	0.90
Correlation (10Y) Calculated over the trailing 10-year period	0.90
Correlation (All Time) Calculated using the full available price history since Nov 15, 2005	0.89

The correlation between TMDIX and MDYG has been stable across timeframes, ranging from 0.87 to 0.90 - a consistent structural relationship.

Return for Risk

TMDIX vs. MDYG — Risk / Return Rank

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

TMDIX

TMDIX Risk / Return Rank: 3
TMDIX Sharpe Ratio Rank: 3
TMDIX Sortino Ratio Rank: 3
TMDIX Omega Ratio Rank: 3
TMDIX Calmar Ratio Rank: 3
TMDIX Martin Ratio Rank: 3

MDYG

MDYG Risk / Return Rank: 62
MDYG Sharpe Ratio Rank: 57
MDYG Sortino Ratio Rank: 57
MDYG Omega Ratio Rank: 53
MDYG Calmar Ratio Rank: 68
MDYG Martin Ratio Rank: 72

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.

TMDIX vs. MDYG - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for AMG TimesSquare Mid Cap Growth Fund (TMDIX) and SPDR S&P 400 Mid Cap Growth ETF (MDYG). 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.

	TMDIX	MDYG	Difference
Sharpe ratio: Return per unit of total volatility	-0.06	1.86	-1.92
Sortino ratio: Return per unit of downside risk	0.06	2.64	-2.58
Omega ratio: Gain probability vs. loss probability	1.01	1.32	-0.32
Calmar ratio: Return relative to maximum drawdown	-0.04	3.30	-3.34
Martin ratio: Return relative to average drawdown	-0.09	13.10	-13.19

TMDIX vs. MDYG - Sharpe Ratio Comparison

The current TMDIX Sharpe Ratio is -0.06, which is lower than the MDYG Sharpe Ratio of 1.86. The chart below compares the historical Sharpe Ratios of TMDIX and MDYG, 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

TMDIX vs. MDYG - Drawdown Comparison

The maximum TMDIX drawdown since its inception was -48.73%, smaller than the maximum MDYG drawdown of -58.44%. Use the drawdown chart below to compare losses from any high point for TMDIX and MDYG.

Drawdown Indicators

	TMDIX	MDYG	Difference
Max Drawdown Largest peak-to-trough decline	-48.73%	-58.44%	+9.71%
Max Drawdown (1Y) Largest decline over 1 year	-25.45%	-9.91%	-15.54%
Max Drawdown (3Y) Largest decline over 3 years	-25.45%	-25.45%	0.00%
Max Drawdown (5Y) Largest decline over 5 years	-30.53%	-29.26%	-1.27%
Max Drawdown (10Y) Largest decline over 10 years	-35.44%	-39.27%	+3.83%
Current Drawdown Current decline from peak	-11.18%	0.00%	-11.18%
Average Drawdown Average peak-to-trough decline	-7.17%	-8.01%	+0.84%
Ulcer Index Depth and duration of drawdowns from previous peaks	12.41%	2.49%	+9.92%

Volatility

TMDIX vs. MDYG - Volatility Comparison

AMG TimesSquare Mid Cap Growth Fund (TMDIX) has a higher volatility of 6.30% compared to SPDR S&P 400 Mid Cap Growth ETF (MDYG) at 5.61%. This indicates that TMDIX's price experiences larger fluctuations and is considered to be riskier than MDYG based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	TMDIX	MDYG	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.30%	5.61%	+0.69%
Volatility (6M) Calculated over the trailing 6-month period	17.83%	13.81%	+4.02%
Volatility (1Y) Calculated over the trailing 1-year period	20.18%	17.59%	+2.59%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	20.51%	20.70%	-0.19%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	21.14%	21.10%	+0.04%

TMDIX vs. MDYG - Expense Ratio Comparison

TMDIX has a 0.98% expense ratio, which is higher than MDYG's 0.15% expense ratio.

Dividends

TMDIX vs. MDYG - Dividend Comparison

TMDIX has not paid dividends to shareholders, while MDYG's dividend yield for the trailing twelve months is around 0.74%.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MDYG SPDR S&P 400 Mid Cap Growth ETF	0.74%	0.75%	0.87%	1.20%	1.16%	0.69%	0.71%	1.21%	1.36%	2.23%	1.25%	2.51%
TMDIX AMG TimesSquare Mid Cap Growth Fund	0.00%	0.00%	8.08%	3.98%	3.69%	29.72%	18.28%	31.06%	16.38%	14.44%	5.90%	7.73%

Frequently Asked Questions

Can I hold both TMDIX and MDYG in my portfolio?

TMDIX and MDYG have a correlation of 0.87, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, TMDIX or MDYG?

TMDIX has higher volatility (6.30%) compared to MDYG (5.61%). In terms of maximum drawdown, TMDIX dropped -48.73% vs MDYG's -58.44%.

Which has better risk-adjusted returns?

MDYG currently has the higher Sharpe Ratio (1.86 vs -0.06), 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.