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 REITs0.99%+0.25 ppHealth Care REITs0.41%+0.10 ppTimber REITs0.10%-0.07 ppMulti-Family Residential REITs0.43%+0.06 ppIndustrial REITs0.27%+0.06 ppData Center REITs0.38%+0.05 ppRetail REITs0.55%+0.03 ppSelf-Storage REITs0.32%+0.02 ppOffice REITs0.21%+0.02 ppHotel & Resort REITs0.08%-0.02 ppOther Specialized REITs0.05%-0.01 ppReal Estate Services0.09%-0.01 ppSingle-Family Residential REITs0.00%+0.00 pp
3 · Sub-industry
Inside Telecom Tower REITs
Telecom Tower REITs · weight
0.99%
Industry change · 12M
+0.25 pp
Telecom Tower REITs · contribution
+0.251 pp
Company participation
100%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
May 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 | $92.3bn | 0.537% | +0.087 pp | +0.167 pp | +54.1% | Yes |
| Crown Castle → CCI | United States | $54.1bn | 0.315% | +0.029 pp | +0.053 pp | +29.8% | Yes |
| SBA Communications → SBAC | United States | $24.5bn | 0.143% | +0.025 pp | +0.032 pp | +36.9% | 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.