MGK vs. IWY

Last updated Jun 4, 2026

MGK (Vanguard Mega Cap Growth ETF) and IWY (iShares Russell Top 200 Growth ETF) are both Large Cap Growth Equities funds - MGK tracks the CRSP US Mega Cap Growth Index while IWY tracks the Russell Top 200 Growth Index. Both are passively managed. Over the past 10 years, MGK returned 19.24%/yr vs 19.57%/yr for IWY. With a 0.98 correlation, they move nearly in lockstep. MGK charges 0.05%/yr vs 0.20%/yr for IWY.

Performance

MGK vs. IWY - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard Mega Cap Growth ETF (MGK) and iShares Russell Top 200 Growth ETF (IWY). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, MGK achieves a 10.01% return, which is significantly higher than IWY's 7.20% return. Both investments have delivered pretty close results over the past 10 years, with MGK having a 19.24% annualized return and IWY not far ahead at 19.57%.

MGK

• 1D: -1.13%
• 1M: 7.26%
• YTD: 10.01%
• 6M: 9.45%
• 1Y: 30.01%
• 3Y*: 26.77%
• 5Y*: 16.25%
• 10Y*: 19.24%

IWY

• 1D: -1.41%
• 1M: 5.83%
• YTD: 7.20%
• 6M: 6.65%
• 1Y: 26.69%
• 3Y*: 25.47%
• 5Y*: 16.45%
• 10Y*: 19.57%

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

MGK vs. IWY - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
MGK Vanguard Mega Cap Growth ETF	10.01%	20.67%	32.94%	51.67%	-33.59%	28.58%	41.01%	37.38%	-2.91%	29.49%
IWY iShares Russell Top 200 Growth ETF	7.20%	18.19%	34.89%	46.49%	-29.91%	31.05%	39.01%	36.20%	-0.72%	31.69%

Correlation

The correlation between MGK and IWY is 0.99 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.99
Correlation (3Y) Calculated over the trailing 3-year period	0.99
Correlation (5Y) Calculated over the trailing 5-year period	0.99
Correlation (10Y) Calculated over the trailing 10-year period	0.99
Correlation (All Time) Calculated using the full available price history since Sep 29, 2009	0.98

The correlation between MGK and IWY has been stable across timeframes, ranging from 0.98 to 0.99 - a consistent structural relationship.

MGK vs. IWY - Sectors Allocation Comparison

Sectors	MGK	IWY
Technology	56.1%	54.9%
Communication Services	17.3%	13.9%
Consumer Cyclical	12.8%	11.4%
Healthcare	4.5%	6.6%
Financial Services	4.5%	5.6%
Real Estate	1.3%	0.3%
Utilities	1.2%	1.1%
Industrials	1.1%	4.0%
Basic Materials	0.7%	0.3%
Consumer Defensive	0.4%	3.0%
Energy	-	0.0%

Return for Risk

MGK vs. IWY — Risk / Return Rank

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

MGK

MGK Risk / Return Rank: 45
MGK Sharpe Ratio Rank: 53
MGK Sortino Ratio Rank: 50
MGK Omega Ratio Rank: 50
MGK Calmar Ratio Rank: 35
MGK Martin Ratio Rank: 38

IWY

IWY Risk / Return Rank: 41
IWY Sharpe Ratio Rank: 49
IWY Sortino Ratio Rank: 46
IWY Omega Ratio Rank: 46
IWY Calmar Ratio Rank: 32
IWY Martin Ratio Rank: 34

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.

MGK vs. IWY - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard Mega Cap Growth ETF (MGK) and iShares Russell Top 200 Growth ETF (IWY). 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.

	MGK	IWY	Difference
Sharpe ratio Return per unit of total volatility	1.86	1.73	+0.13
Sortino ratio Return per unit of downside risk	2.53	2.36	+0.17
Omega ratio Gain probability vs. loss probability	1.32	1.30	+0.02
Calmar ratio Return relative to maximum drawdown	1.79	1.61	+0.18
Martin ratio Return relative to average drawdown	6.15	5.26	+0.90
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

MGK vs. IWY - Sharpe Ratio Comparison

The current MGK Sharpe Ratio is 1.86, which is comparable to the IWY Sharpe Ratio of 1.73. The chart below compares the historical Sharpe Ratios of MGK and IWY, 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

	MGK	IWY	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.86	1.73	+0.13
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.72	0.77	-0.05
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.88	0.94	-0.05
Sharpe Ratio (All Time) Calculated using the full available price history	0.66	0.92	-0.26

Drawdowns

MGK vs. IWY - Drawdown Comparison

The maximum MGK drawdown since its inception was -47.97%, which is greater than IWY's maximum drawdown of -32.68%. Use the drawdown chart below to compare losses from any high point for MGK and IWY.

Drawdown Indicators

	MGK	IWY	Difference
Max Drawdown Largest peak-to-trough decline	-47.97%	-32.68%	-15.29%
Max Drawdown (1Y) Largest decline over 1 year	-16.85%	-16.63%	-0.22%
Max Drawdown (3Y) Largest decline over 3 years	-23.36%	-23.22%	-0.14%
Max Drawdown (5Y) Largest decline over 5 years	-36.01%	-32.68%	-3.33%
Max Drawdown (10Y) Largest decline over 10 years	-36.01%	-32.68%	-3.33%
Current Drawdown Current decline from peak	-1.43%	-1.82%	+0.39%
Average Drawdown Average peak-to-trough decline	-7.47%	-4.75%	-2.72%
Ulcer Index Depth and duration of drawdowns from previous peaks	4.89%	5.09%	-0.20%

Volatility

MGK vs. IWY - Volatility Comparison

Vanguard Mega Cap Growth ETF (MGK) has a higher volatility of 4.01% compared to iShares Russell Top 200 Growth ETF (IWY) at 3.69%. This indicates that MGK's price experiences larger fluctuations and is considered to be riskier than IWY based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MGK	IWY	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.01%	3.69%	+0.32%
Volatility (6M) Calculated over the trailing 6-month period	12.37%	11.65%	+0.72%
Volatility (1Y) Calculated over the trailing 1-year period	16.23%	15.54%	+0.69%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	22.63%	21.48%	+1.15%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	21.88%	20.97%	+0.91%

MGK vs. IWY - Expense Ratio Comparison

MGK has a 0.05% expense ratio, which is lower than IWY's 0.20% 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

MGK vs. IWY - Dividend Comparison

MGK's dividend yield for the trailing twelve months is around 0.32%, less than IWY's 0.33% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
IWY iShares Russell Top 200 Growth ETF	0.33%	0.36%	0.42%	0.68%	0.88%	0.50%	0.71%	1.06%	1.32%	1.26%	1.51%	1.58%
MGK Vanguard Mega Cap Growth ETF	0.32%	0.35%	0.43%	0.50%	0.70%	0.41%	0.65%	0.85%	1.12%	1.23%	1.53%	1.43%

Frequently Asked Questions

Can I hold both MGK and IWY in my portfolio?

With a correlation of 0.99, MGK and IWY 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, MGK or IWY?

MGK has higher volatility (4.01%) compared to IWY (3.69%). In terms of maximum drawdown, MGK dropped -47.97% vs IWY's -32.68%.

Which ETF is better, MGK or IWY?

On 10-year performance, IWY leads with 19.57% vs 19.24% for MGK. On fees, MGK is cheaper at 0.05% per year. On volatility, IWY has been the lower-risk option at 3.69%. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF has performed better, MGK or IWY?

Over the 10-year period, IWY has performed better with a 19.57% return vs 19.24%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

Which ETF is cheaper, MGK or IWY?

MGK is cheaper with a 0.05% expense ratio, compared with 0.20% for IWY.

Which ETF pays a higher dividend yield, MGK or IWY?

MGK and IWY have nearly identical dividend yields, around 0.32%.

What is the main difference between MGK and IWY?

MGK tracks CRSP US Mega Cap Growth Index, while IWY tracks Russell Top 200 Growth Index. They also come from different issuers: Vanguard and iShares. Their fees differ too: 0.05% for MGK and 0.20% for IWY.

Which has better risk-adjusted returns?

MGK currently has the higher Sharpe Ratio (1.86 vs 1.73), 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.