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 Materials
Paper & Plastic Packaging Products & Materials28.54%+28.18 ppIndustrial Gases0.41%-0.24 ppSpecialty Chemicals0.36%-0.19 ppGold0.19%+0.09 ppConstruction Materials0.22%+0.08 ppFertilizers & Agricultural Chemicals0.11%-0.04 ppCommodity Chemicals0.03%-0.03 ppSteel0.09%-0.02 ppCopper0.13%+0.02 ppMetal, Glass & Plastic Containers0.02%-0.01 pp
3 · Sub-industry
Inside Construction Materials
Construction Materials · weight
0.22%
Industry change · 12M
+0.08 pp
Construction Materials · contribution
+0.083 pp
Company participation
33%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Feb 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 |
|---|---|---|---|---|---|---|---|
| CRH plc → CRH | United States | $80.2bn | 0.110% | +0.110 pp | +0.110 pp | +17.9% | Yes |
| Vulcan Materials Company → VMC | United States | $40.5bn | 0.056% | -0.022 pp | -0.018 pp | +26.3% | No |
| Martin Marietta Materials → MLM | United States | $40.8bn | 0.056% | -0.018 pp | -0.010 pp | +40.8% | 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.