MDY vs VIMAX: 0% overlap
SPDR S&P MidCap 400 ETF Trust and Vanguard Mid-Cap Index Admiral share 0.1% 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 VIMAX hold 1 of the same securities. The ten contributing most to the overlap figure:
| Holding | in MDY | in VIMAX | Δ |
|---|---|---|---|
| BURL | 0.6% | 0.1% | 0.5% |
Where MDY and VIMAX 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 | VIMAX | Δ |
|---|---|---|---|
| Industrials | 25.4% | 19.6% | +5.8pp |
| Utilities | 3.1% | 8.4% | −5.2pp |
| Energy | 4.9% | 7.3% | −2.4pp |
| Information Technology | 13.8% | 16.1% | −2.3pp |
| Health Care | 9.7% | 7.8% | +1.9pp |
| Real Estate | 6.9% | 5.1% | +1.8pp |
| Consumer Staples | 3.1% | 4.9% | −1.8pp |
| Consumer Discretionary | 10.2% | 8.9% | +1.3pp |
Δ is MDY minus VIMAX, 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
98.3% of MDY by weight, held in no part of VIMAX.
99.9% of VIMAX 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 | VIMAX | |
|---|---|---|
| Top 10 holdings | 7.6% | 9.5% |
| Positions held | 400 | 283 |
| Cost per $10,000 held, per year | $23 | $5 |
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 VIMAX overlap?
MDY and VIMAX overlap 0.1% by portfolio weight — largely distinct portfolios. They share 1 holdings. The figure comes from current issuer holdings files (MDY as of 2026-07-23, VIMAX as of 2026-06-30).
How is the overlap between MDY and VIMAX 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 VIMAX 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 VIMAX?
That depends on your goals — we state facts, not advice. At 0.1% overlap, each fund still contributes meaningfully distinct exposure.
What does MDY own that VIMAX doesn't?
MDY holds 400 positions and VIMAX holds 283; 398 of MDY's positions don't appear in VIMAX at all, and they are 98.3% 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, VIMAX as of 2026-06-30. Weights are fractions of each fund. Diagnostics, not advice.