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 REITs0.48%-0.26 ppRetail REITs0.32%-0.17 ppData Center REITs0.18%-0.15 ppMulti-Family Residential REITs0.22%-0.11 ppTimber REITs0.06%-0.10 ppHealth Care REITs0.21%-0.09 ppSelf-Storage REITs0.17%-0.09 ppOffice REITs0.11%-0.08 ppIndustrial REITs0.13%-0.07 ppHotel & Resort REITs0.04%-0.04 ppReal Estate Services0.05%-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
0.48%
Industry change · 12M
-0.26 pp
Telecom Tower REITs · contribution
-0.264 pp
Company participation
0%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Dec 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 | $69.7bn | 0.249% | +0.045 pp | -0.112 pp | +9.5% | No |
| Crown Castle → CCI | United States | $45.1bn | 0.161% | +0.014 pp | -0.100 pp | +0.2% | No |
| SBA Communications → SBAC | United States | $18.3bn | 0.066% | +0.007 pp | -0.051 pp | -7.2% | 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.