# Calculation

Intratec's indexes and cost estimates are derived from underlying raw data using transparent, reproducible models.

## Cost Indexes

Plant construction and labor cost indexes are calculated as weighted composites of component costs. Weights reflect the typical cost structure of industrial facilities in each economy.

## Normalization

All monetary values are expressed in USD. Local currency values are converted using period-average exchange rates published by the IMF.

## Historical Revisions

When source agencies revise historical data, Intratec propagates those revisions forward through the model. Revision notes are published alongside each affected dataset release.