Observatory · observe first
Follow the allocation change
Matched S&P 500 members → sector → industry → sub-industry → company. Each step uses the same percentage points.
Historical time machine
Historical observation
20182026
1 · Sector
Weight and 12M allocation change
2 · Industry
Inside Real Estate
Telecom Tower REITs0.97%+0.56 ppHealth Care REITs0.43%+0.26 ppMulti-Family Residential REITs0.44%+0.24 ppRetail REITs0.52%+0.23 ppData Center REITs0.40%+0.22 ppIndustrial REITs0.29%+0.17 ppSelf-Storage REITs0.31%+0.16 ppOffice REITs0.20%+0.10 ppReal Estate Services0.09%+0.05 ppTimber REITs0.11%+0.03 ppOther Specialized REITs0.05%+0.02 ppHotel & Resort REITs0.07%+0.02 ppSingle-Family Residential REITs0.00%+0.00 pp
3 · Sub-industry
Inside Telecom Tower REITs
Telecom Tower REITs · weight
0.97%
Industry change · 12M
+0.56 pp
Telecom Tower REITs · contribution
+0.562 pp
Company participation
100%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Sep 2019 · sorted by absolute contribution to 12-month change
| Company | Country | Market cap | Universe weight | 3M contribution | 12M contribution | 12M price return | Above 6M weight average |
|---|---|---|---|---|---|---|---|
| American Tower → AMT | United States | $97.9bn | 0.520% | +0.033 pp | +0.316 pp | +55.1% | Yes |
| Crown Castle → CCI | United States | $57.8bn | 0.307% | +0.015 pp | +0.160 pp | +29.4% | Yes |
| SBA Communications → SBAC | United States | $27.3bn | 0.145% | +0.008 pp | +0.086 pp | +50.3% | Yes |
Company contributions use weights among matched S&P 500 members and add through each level without rescaling. Companies without matched shares and prices are omitted. These observations do not establish official index weights or actual fund flows.