CSI All Share Index: What It Measures and How It Is Built

Direct Answer

The CSI All Share Index is a rule-based measurement of broad Chinese equity benchmark, maintained by China Securities Index Co.. Like every index it owns nothing: it is a number produced by applying a published weighting formula to a selected list of companies, revised on a schedule the provider sets.

What this index covers

The CSI All Share Index covers broad Chinese equity benchmark, within the China market. China Securities Index Co. defines which securities are eligible, how they are selected from that pool, and how much each one contributes to the published number.

The index name does not state a fixed company count, so the number of constituents follows the eligibility rules rather than a target.

How constituents are weighted

Free float adjusted market capitalisation weighted: security price times free float adjusted shares, summed and divided by a divisor.

The weighting method is the single biggest driver of how an index behaves. Two indexes covering the same market can diverge for years purely because they weight differently, which is why comparing index levels without knowing the method tells you very little.

What qualifies for inclusion

All securities listed on the Shanghai, Shenzhen or Beijing stock exchanges that are not ST or *ST are in the universe, and every security in the universe is selected as a constituent. There is no ranking, size cut off or liquidity screen.

Eligibility rules are the part of an index most readers never look at and the part that decides what it can possibly measure. A screen that excludes a whole sector, or admits only one listing venue, shapes the result far more than any day of trading does.

How long a listing must exist first

STAR Market securities must have been listed for more than one year and Beijing Stock Exchange securities for more than two years. Other securities need more than one quarter, unless the security ranks in the top 30 by average daily market capitalisation since listing.

A seasoning rule is why a large new listing does not appear in an index the week it starts trading. It is a deliberate lag, and it means an index can under-represent a fast-growing part of the market for months at a time.

When the membership is revised

Adjusted and rebalanced semi-annually, effective the next trading day after the second Friday of June and December. Special events are reviewed as they occur, and delisted securities are deleted from the constituents.

Reconstitution is the one date an index changes shape by design rather than by price. Funds tracking it have to trade toward the new membership, which is why the schedule matters to anyone holding the tracker rather than only to the provider.

The rule that surprises people

Every eligible non-ST and non-*ST security on the SSE, SZSE and BSE that meets the listing time rules is a constituent, and delisted securities are deleted.

References

• China Securities Index Co.: China Securities Index Co., Methodology of CSI All Share Index, as published 2023. Every rule described on this page is taken from this document.

Current CSI All Share Index constituents

China Securities Index Co. publishes and licenses the CSI All Share Index constituent list. Swoopr does not republish it here. The provider's own page is the authoritative source for current membership and weights.

China Securities Index Co.: official CSI All Share Index page

Related reading

• All stock market indexes: how indexes are built, weighted and revised.
• Emerging Markets indexes: others covering the same region.
• Index concentration: measuring how much of an index sits in its largest holdings.
• Index rebalancing and inclusion effects: what happens to a stock when index membership changes.

Frequently Asked Questions