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
Self-Storage REITs0.32%+0.06 ppRetail REITs0.55%+0.05 ppMulti-Family Residential REITs0.37%+0.03 ppTelecom Tower REITs0.77%+0.03 ppHealth Care REITs0.34%+0.03 ppIndustrial REITs0.21%+0.01 ppOffice REITs0.20%+0.01 ppData Center REITs0.35%+0.01 ppReal Estate Services0.10%+0.01 ppOther Specialized REITs0.06%+0.01 ppHotel & Resort REITs0.09%+0.01 ppTimber REITs0.17%+0.01 ppSingle-Family Residential REITs0.00%+0.00 pp
3 · Sub-industry
Inside Telecom Tower REITs
Telecom Tower REITs · weight
0.77%
Industry change · 12M
+0.03 pp
Telecom Tower REITs · contribution
+0.033 pp
Company participation
100%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Jun 2018 · 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 | $63.7bn | 0.386% | -0.007 pp | +0.025 pp | -1.3% | Yes |
| Crown Castle → CCI | United States | $44.7bn | 0.271% | -0.002 pp | +0.010 pp | -2.5% | Yes |
| SBA Communications → SBAC | United States | $19.0bn | 0.115% | -0.007 pp | -0.002 pp | -5.4% | 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.