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 REITs0.82%-0.32 ppData Center REITs0.39%-0.11 ppMulti-Family Residential REITs0.28%-0.07 ppIndustrial REITs0.31%-0.06 ppOffice REITs0.16%-0.04 ppReal Estate Services0.10%+0.02 ppTimber REITs0.11%+0.01 ppRetail REITs0.32%+0.01 ppSelf-Storage REITs0.25%+0.00 ppHealth Care REITs0.26%-0.00 ppOther Specialized REITs0.04%+0.00 ppHotel & Resort REITs0.05%-0.00 ppSingle-Family Residential REITs0.00%+0.00 pp
3 · Sub-industry
Inside Telecom Tower REITs
Telecom Tower REITs · weight
0.82%
Industry change · 12M
-0.32 pp
Telecom Tower REITs · contribution
-0.319 pp
Company participation
100%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Apr 2021 · 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 | $113.3bn | 0.411% | +0.169 pp | -0.180 pp | +9.2% | Yes |
| Crown Castle → CCI | United States | $81.5bn | 0.296% | +0.131 pp | -0.076 pp | +22.4% | Yes |
| SBA Communications → SBAC | United States | $32.8bn | 0.119% | +0.047 pp | -0.063 pp | +4.1% | 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.