Definitions
In plain terms
Under a common diffusion convention, rising sectors count one, unchanged sectors one half, and falling sectors zero.
Technical
The Fintech Builder adaptation must define sector signal, taxonomy, eligibility, weights, unchanged tolerance, denominator, and timestamp.
Scope
The Conference Board's general diffusion math does not make this an official Conference Board market-sector indicator.
Formula
Sector diffusion = 100 * (N_up + 0.5 * N_unchanged) / N_eligibleSDI=100\frac{N_{up}+0.5N_{unchanged}}{N_{eligible}}| Symbol | Meaning | Unit |
|---|---|---|
N_up | eligible sectors classified as increasing | sectors |
N_unchanged | eligible sectors classified as unchanged | sectors |
N_eligible | eligible classified sectors | sectors |
Output unit: percent
Examples
- A Fintech Builder lesson can compute or identify Sector Diffusion Index only after declaring its inputs, timing, and edge-case rules.
Common misconceptions
- The Conference Board's general diffusion math does not make this an official Conference Board market-sector indicator.
Concept relationships
Prerequisites
Where this concept is used
Evidence and governance
- Business Cycle Indicators: Diffusion Indexes The Conference Board · first party methodology
Supports: preferred label, short definition, technical definition, formula
Limits: Applying the general diffusion construction to sectors or factor groups is a declared Fintech Builder adaptation.
- Reviewed by
- fintech-builder-batch-005
- Last reviewed
- 2026-07-27
- Next review
- 2027-07-27
- Record status
- evidence reviewed
This record is evidence-reviewed and readable, but not yet promoted to published — it is served noindex,follow and excluded from the sitemap.