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
Retail REITs0.54%+0.04 ppSelf-Storage REITs0.29%+0.04 ppMulti-Family Residential REITs0.36%+0.03 ppHealth Care REITs0.32%+0.02 ppTelecom Tower REITs0.76%+0.02 ppData Center REITs0.35%+0.02 ppTimber REITs0.15%-0.01 ppReal Estate Services0.10%+0.01 ppOffice REITs0.19%+0.01 ppIndustrial REITs0.20%+0.01 ppOther Specialized REITs0.06%+0.01 ppHotel & Resort REITs0.09%+0.00 ppSingle-Family Residential REITs0.00%+0.00 pp
3 · Sub-industry
Inside Telecom Tower REITs
Telecom Tower REITs · weight
0.76%
Industry change · 12M
+0.02 pp
Telecom Tower REITs · contribution
+0.016 pp
Company participation
67%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Jul 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 | $65.3bn | 0.381% | +0.012 pp | +0.020 pp | +1.5% | Yes |
| SBA Communications → SBAC | United States | $18.2bn | 0.106% | -0.008 pp | -0.011 pp | -9.3% | No |
| Crown Castle → CCI | United States | $46.0bn | 0.268% | +0.016 pp | +0.007 pp | +0.3% | 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.