State Street SPDR Portfolio Mortgage Backed Bond ETF
State Street·Tracks Bloomberg US MBS Index·Inception Jan 15, 2009
Composite score
Based on a 0.040% expense ratio.
Based on $7.14B in net assets.
Top-10 holdings represent 13.8% of net assets.
US Aggregate Bond base · ETF wrapper · 4.23% TTM yield.
The composite is a weighted average of the four core sub-scores above (cost, tax efficiency, liquidity, concentration). Missing sub-scores fall back to the per-category median when the category has at least 50% data coverage, so funds without (e.g.) parsed N-PORT holdings aren't accidentally boosted by renormalization. Tracking quality is shown where computable but isn't currently part of the composite weighting. Seemethodologyfor formulas, thetracking-qualitypartial-coverage rationale, and the dimensions we deliberatelydon't score(methodology v0.5.1).
Use SPMB in our tools
Tool · Look-through
See what SPMB actually holds, in a portfolio
Add your other funds and weights; every underlying position is summed across the basket.
Tool · Cost
Compare SPMB's fee against another fund
Compounds the 0.040% expense ratio against a peer over decades.
Tool · Overlap
Compare SPMB's holdings with peers
Pairwise holdings heatmap, pre-loaded with similar US Aggregate Bond funds.
Tool · TLH
Find a tax-loss harvesting partner for SPMB
Ranks every catalog fund by holdings overlap, flags wash-sale risk.
Tool · Placement
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Asset-location optimizer — places each fund in taxable / tax-deferred / Roth.
Top holdings
| # | Holding | Weight |
|---|---|---|
| 1 | State Street Global Advisors | 7.16% |
| 2 | Freddie Mac | 1.17% |
| 3 | State Street Global Advisors | 1.03% |
| 4 | Fannie Mae | 0.79% |
| 5 | Freddie Mac | 0.76% |
| 6 | UMBS, TBA | 0.63% |
| 7 | Freddie Mac | 0.61% |
| 8 | Freddie Mac | 0.55% |
| 9 | Government National Mortgage Association | 0.55% |
| 10 | Fannie Mae | 0.51% |
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