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 REITs0.41%-0.33 ppRetail REITs0.30%-0.20 ppData Center REITs0.18%-0.15 ppMulti-Family Residential REITs0.20%-0.13 ppHealth Care REITs0.18%-0.13 ppSelf-Storage REITs0.15%-0.11 ppTimber REITs0.08%-0.08 ppIndustrial REITs0.12%-0.08 ppOffice REITs0.10%-0.08 ppReal Estate Services0.05%-0.04 ppHotel & Resort REITs0.05%-0.04 ppOther Specialized REITs0.03%-0.02 ppSingle-Family Residential REITs0.00%+0.00 pp
3 · Sub-industry
Inside Telecom Tower REITs
Telecom Tower REITs · weight
0.41%
Industry change · 12M
-0.33 pp
Telecom Tower REITs · contribution
-0.330 pp
Company participation
0%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Sep 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 | $64.1bn | 0.204% | -0.182 pp | -0.157 pp | -0.0% | No |
| Crown Castle → CCI | United States | $46.2bn | 0.147% | -0.124 pp | -0.114 pp | +1.7% | No |
| SBA Communications → SBAC | United States | $18.4bn | 0.059% | -0.057 pp | -0.058 pp | -7.9% | No |
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.