Direct Answer
The CSI 500 is a rule-based measurement of Chinese mid-cap 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 500 covers Chinese mid-cap 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 name states a target of 500 companies. A target is not a guarantee of the exact count on any given day: corporate actions, dual share classes and pending additions all move the real number around it.
How constituents are weighted
Free float adjusted market capitalisation weighted: security price times free float adjusted shares times a weight factor, summed and divided by a divisor, with a base value of 1000 at the base date of December 31, 2004. Free float details follow the CSI general calculation methodology.
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
The universe is the CSI 300 universe. CSI 300 constituents and the 300 largest securities by average daily total market capitalisation over the past year are removed, the bottom 20% of the rest by average daily trading value are dropped, and the top 500 by average daily total market capitalisation are selected.
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.
When the membership is revised
Adjusted semi-annually, effective the next trading day after the second Friday of June and December. No more than 10% of constituents change at a review. A buffer zone gives priority to new candidates ranked in the top 400 and existing constituents ranked in the top 600, and a reserve list is usually about 5% of the constituent count.
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
The index is defined by exclusion: it holds what remains after the CSI 300 members and the 300 largest securities are removed, and the liquidity screen is applied only after that step. When CSI 300 and CSI 500 constituents change, the CSI 200, CSI 700 and CSI 800 constituents are adjusted accordingly.
References
- China Securities Index Co.: China Securities Index Co., Methodology of CSI 200, CSI 500, CSI 700 and CSI 800 Indices, as published 2022. Every rule described on this page is taken from this document.
Current CSI 500 constituents
China Securities Index Co. publishes and licenses the CSI 500 constituent list. Swoopr does not republish it here. The provider's own page is the authoritative source for current membership and weights.
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
Who maintains the CSI 500?
China Securities Index Co. maintains the CSI 500 and publishes the methodology document that defines its eligibility and weighting rules.
What does the CSI 500 measure?
It measures Chinese mid-cap equity benchmark. The index is a calculated number applying a weighting formula to a selected list of companies, and it holds nothing itself.
Where can I see the current CSI 500 constituents?
China Securities Index Co. publishes the current constituent list. Swoopr does not republish it, because index providers license constituent data and Swoopr holds no such licence.