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 Industrials
Industrial Machinery & Supplies & Components1.02%-0.25 ppConstruction Machinery & Heavy Transportation Equipment0.67%-0.20 ppHeavy Electrical Equipment0.22%+0.20 ppRail Transportation0.60%-0.18 ppElectrical Components & Equipment0.56%-0.17 ppAir Freight & Logistics0.37%-0.16 ppDiversified Support Services0.37%+0.12 ppPassenger Ground Transportation0.36%-0.08 ppTrading Companies & Distributors0.15%-0.05 ppAerospace & Defense2.38%+0.03 ppConstruction & Engineering0.12%-0.03 ppHuman Resource & Employment Services0.43%+0.02 ppResearch & Consulting Services0.17%-0.01 ppAgricultural & Farm Machinery0.30%-0.01 ppPassenger Airlines0.17%-0.01 ppIndustrial Conglomerates0.61%-0.01 ppEnvironmental & Facilities Services0.52%-0.01 ppCargo Ground Transportation0.12%-0.00 ppData Processing & Outsourced Services0.07%+0.00 ppBuilding Products0.56%-0.00 pp
3 · Sub-industry
Inside Rail Transportation
Rail Transportation · weight
0.60%
Industry change · 12M
-0.18 pp
Rail Transportation · contribution
-0.178 pp
Company participation
33%
of industry constituents above their 6M weight average
4 · Companies driving this sub-industry
Mar 2025 · 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 |
|---|---|---|---|---|---|---|---|
| Union Pacific Corporation → UNP | United States | $142.8bn | 0.339% | +0.025 pp | -0.077 pp | -1.8% | Yes |
| CSX Corporation → CSX | United States | $55.8bn | 0.132% | -0.009 pp | -0.069 pp | -19.4% | No |
| Norfolk Southern → NSC | United States | $53.6bn | 0.127% | +0.007 pp | -0.032 pp | -5.0% | 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.