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 REITs0.22%-0.15 ppHealth Care REITs0.38%+0.07 ppReal Estate Services0.09%-0.07 ppMulti-Family Residential REITs0.15%-0.04 ppSelf-Storage REITs0.15%-0.03 ppHotel & Resort REITs0.08%-0.02 ppOffice REITs0.03%-0.02 ppSingle-Family Residential REITs0.03%-0.01 ppTimber REITs0.03%-0.01 ppIndustrial REITs0.22%+0.01 ppData Center REITs0.29%-0.01 ppRetail REITs0.28%-0.00 ppOther Specialized REITs0.07%+0.00 pp
3 · Sub-industry
Inside Telecom Tower REITs
Telecom Tower REITs · weight
0.22%
Industry change · 12M
-0.15 pp
Telecom Tower REITs · contribution
-0.152 pp
Company participation
33%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Jun 2026 · 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 | $76.2bn | 0.132% | +0.015 pp | -0.091 pp | -23.1% | No |
| Crown Castle → CCI | United States | $33.1bn | 0.057% | +0.006 pp | -0.039 pp | -22.7% | No |
| SBA Communications → SBAC | United States | $18.7bn | 0.033% | +0.006 pp | -0.022 pp | -23.1% | 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.