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 & Materials0.17%-0.21 ppIndustrial Gases0.49%-0.11 ppSpecialty Chemicals0.41%-0.09 ppConstruction Materials0.21%+0.06 ppGold0.22%+0.05 ppCopper0.18%+0.05 ppSteel0.15%+0.04 ppFertilizers & Agricultural Chemicals0.14%-0.02 ppMetal, Glass & Plastic Containers0.03%-0.00 ppCommodity Chemicals0.04%+0.00 pp
3 · Sub-industry
Inside Construction Materials
Construction Materials · weight
0.21%
Industry change · 12M
+0.06 pp
Construction Materials · contribution
+0.058 pp
Company participation
0%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Aug 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 | $62.7bn | 0.104% | -0.022 pp | +0.104 pp | -15.6% | No |
| Martin Marietta Materials → MLM | United States | $31.2bn | 0.052% | -0.009 pp | -0.025 pp | -15.4% | No |
| Vulcan Materials Company → VMC | United States | $35.0bn | 0.058% | -0.005 pp | -0.021 pp | -6.7% | 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.