How the AI P/E ratio is built

Methodology version 1.0. List date Oct 2, 2026.

This index

The public members' combined market cap over their combined trailing twelve-month net income, loss-makers included. Private members are left out.
Earnings are as first reported, and a company whose latest period ended more than fifteen months ago has none. A P/E is shown only when companies with earnings on file make up at least 80% of the market cap it covers.
The same figure for six groups, from each company's role in the AI value chain: semiconductors, software, hardware and data centres, cloud and models, power and materials, robotics and physical AI.

Every index is built from the same list of US companies building AI, chosen by our editors. A change to the list applies from its own date and never rewrites earlier days.
Share counts and earnings come from filings made by each day, so a later restatement never changes an old value.
Before the list date the values are a back-test of the companies picked that day, each from its first trading day.
A day whose prices cover too little of the index, or whose level moves more than 8%, is held for review before it is published.

Sources: company filings, exchange prices and secondary-market trades.