MDY vs VFMO: 15% overlap
SPDR S&P MidCap 400 ETF Trust and Vanguard U.S. Momentum Factor ETF share 15.1% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
Different holding dates. These holdings were published about 4 months apart — VFMO as of 2026-03-31, the rest through 2026-07-27. Each fund is compared using its most recent file, so any trading in between shows up as a difference.
You would hold two tickers and get the diversification of 1.8. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
MDY and VFMO hold 100 of the same securities. The ten contributing most to the overlap figure:
| Holding | in MDY | in VFMO | Δ |
|---|---|---|---|
| ROIV | 0.4% | 0.5% | 0.0% |
| FTI | 0.8% | 0.3% | 0.5% |
| FIVE | 0.3% | 0.3% | 0.0% |
| STRL | 0.5% | 0.3% | 0.2% |
| SGI | 0.4% | 0.3% | 0.1% |
| AEIS | 0.3% | 0.3% | 0.0% |
| NXT | 0.4% | 0.3% | 0.1% |
| CDE | 0.4% | 0.3% | 0.2% |
| DY | 0.4% | 0.3% | 0.1% |
| MTZ | 0.6% | 0.3% | 0.3% |
Where MDY and VFMO 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 | VFMO | Δ |
|---|---|---|---|
| Health Care | 10.0% | 22.3% | −12.3pp |
| Financials | 15.0% | 6.3% | +8.7pp |
| Real Estate | 6.9% | 0.1% | +6.8pp |
| Information Technology | 13.4% | 17.0% | −3.6pp |
| Utilities | 3.1% | 0.0% | +3.0pp |
| Energy | 4.7% | 7.7% | −3.0pp |
| Consumer Discretionary | 10.3% | 7.8% | +2.5pp |
| Communication Services | 1.6% | 3.4% | −1.8pp |
Δ is MDY minus VFMO, 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
65.0% of MDY by weight, held in no part of VFMO.
84.8% of VFMO 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 | VFMO | |
|---|---|---|
| Top 10 holdings | 7.4% | 10.2% |
| Positions held | 400 | 672 |
| Cost per $10,000 held, per year | $23 | $13 |
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 VFMO overlap?
MDY and VFMO overlap 15.1% by portfolio weight — moderate overlap. They share 100 holdings. The figure comes from current issuer holdings files (MDY as of 2026-07-27, VFMO as of 2026-03-31).
How is the overlap between MDY and VFMO 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 VFMO 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 VFMO?
That depends on your goals — we state facts, not advice. At 15.1% overlap, each fund still contributes meaningfully distinct exposure.
What does MDY own that VFMO doesn't?
MDY holds 400 positions and VFMO holds 672; 299 of MDY's positions don't appear in VFMO at all, and they are 65.0% of MDY by weight.
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Related comparisons
Sources: issuer holdings files, MDY as of 2026-07-27, VFMO as of 2026-03-31. Weights are fractions of each fund. Diagnostics, not advice.