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 REITs0.85%+0.11 ppHealth Care REITs0.38%+0.10 ppRetail REITs0.58%+0.09 ppMulti-Family Residential REITs0.40%+0.08 ppIndustrial REITs0.26%+0.06 ppTimber REITs0.11%-0.05 ppData Center REITs0.33%+0.02 ppOffice REITs0.21%+0.02 ppSelf-Storage REITs0.28%+0.02 ppOther Specialized REITs0.06%+0.01 ppReal Estate Services0.10%+0.00 ppHotel & Resort REITs0.08%+0.00 ppSingle-Family Residential REITs0.00%+0.00 pp
3 · Sub-industry
Inside Telecom Tower REITs
Telecom Tower REITs · weight
0.85%
Industry change · 12M
+0.11 pp
Telecom Tower REITs · contribution
+0.107 pp
Company participation
100%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Feb 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 | $77.7bn | 0.450% | +0.210 pp | +0.082 pp | +29.2% | Yes |
| Crown Castle → CCI | United States | $49.3bn | 0.286% | +0.128 pp | +0.018 pp | +12.2% | Yes |
| SBA Communications → SBAC | United States | $20.3bn | 0.118% | +0.054 pp | +0.007 pp | +14.8% | 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.