MDY vs VOOG: 0% overlap
SPDR S&P MidCap 400 ETF Trust and Vanguard S&P 500 Growth ETF share 0.0% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
You would hold two tickers and get the diversification of 2.0. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
MDY and VOOG hold 0 of the same securities. The ten contributing most to the overlap figure:
| Holding | in MDY | in VOOG | Δ |
|---|
Where MDY and VOOG differ
Sector weights as a share of each fund, ordered by the size of the gap rather than the size of the sector — two funds that overlap heavily still usually diverge somewhere.
| Sector | MDY | VOOG | Δ |
|---|---|---|---|
| Information Technology | 13.8% | 52.2% | −38.4pp |
| Industrials | 25.4% | 6.9% | +18.5pp |
| Communication Services | 1.5% | 15.2% | −13.7pp |
| Financials | 14.8% | 8.5% | +6.3pp |
| Real Estate | 6.9% | 0.6% | +6.3pp |
| Materials | 5.4% | 0.3% | +5.2pp |
| Energy | 4.9% | 0.0% | +4.9pp |
| Health Care | 9.7% | 6.2% | +3.5pp |
Δ is MDY minus VOOG, in percentage points. Sector data is not published by every issuer, so “Unclassified” is a real category rather than a gap in the table.
What each fund holds alone
98.9% of MDY by weight, held in no part of VOOG.
100.0% of VOOG by weight, held in no part of MDY.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| MDY | VOOG | |
|---|---|---|
| Top 10 holdings | 7.6% | 56.4% |
| Positions held | 400 | 148 |
| Cost per $10,000 held, per year | $23 | $7 |
Cost is the expense ratio applied to $10,000; it excludes any brokerage commission, bid-ask spread or tax consequence. Figures are facts about the funds, not a suggestion about which to hold.
Frequently asked
How much do MDY and VOOG overlap?
MDY and VOOG overlap 0.0% by portfolio weight — largely distinct portfolios. They share 0 holdings. The figure comes from current issuer holdings files (MDY as of 2026-07-23, VOOG as of 2026-06-30).
How is the overlap between MDY and VOOG calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If MDY holds a stock at 6% and VOOG holds the same stock at 4%, 4% counts as shared. The result is bounded between 0% and 100%, and it is computed after looking through any fund-of-funds to the underlying holdings.
Is it redundant to hold both MDY and VOOG?
That depends on your goals — we state facts, not advice. At 0.0% overlap, each fund still contributes meaningfully distinct exposure.
What does MDY own that VOOG doesn't?
MDY holds 400 positions and VOOG holds 148; 399 of MDY's positions don't appear in VOOG at all, and they are 98.9% of MDY by weight.
You probably hold more than two funds
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Related comparisons
Sources: issuer holdings files, MDY as of 2026-07-23, VOOG as of 2026-06-30. Weights are fractions of each fund. Diagnostics, not advice.