--- title: "All Share Price Index: Methodology" description: "All Share Price Index is maintained by Colombo Stock Exchange / S&P DJI and covers broad Sri Lankan equity benchmark. How it weights its constituents." canonical: https://www.getswoopr.com/stocks/indexes/aspi/ source: "Swoopr Investment: https://www.getswoopr.com" --- # All Share Price Index: What It Measures and How It Is Built ## Direct Answer > The All Share Price Index is a rule-based measurement of broad Sri Lankan equity benchmark, maintained by Colombo Stock Exchange / S&P DJI. 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 All Share Price Index covers broad Sri Lankan equity benchmark, within the Sri Lanka market. Colombo Stock Exchange / S&P DJI 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 Weighted by public float adjusted market capitalization, with a 5% cap on any company applied at each quarterly rebalancing. Excess weight is distributed proportionately among the remaining constituents. 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 Designed to cover all listed securities on the Colombo Stock Exchange. Both voting and non-voting share classes are eligible for inclusion. 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 Rebalanced quarterly, effective after the third Friday of March, June, September and December. Companies heading toward delisting that are not trading at the time of rebalancing are excluded from it. 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 Until the January 2022 change, the index weighted every company by its full market capitalization regardless of how much of it the public held. Weights now depend on the public holding percentages that companies disclose, and the previous disclosure is reused if a new one is missing. ## References - [Colombo Stock Exchange / S&P DJI: Colombo Stock Exchange Index Methodology Version 04](https://cdn.cse.lk/pdf/Index-Methodologies-of-Colombo-Stock-Exchanhge.pdf), as published 2021. Every rule described on this page is taken from this document. ## Current All Share Price Index constituents Colombo Stock Exchange / S&P DJI publishes and licenses the All Share Price Index constituent list. Swoopr does not republish it here. The provider's own page is the authoritative source for current membership and weights. [Colombo Stock Exchange / S&P DJI: official All Share Price Index page](https://www.cse.lk/) ## Related reading - [All stock market indexes](https://www.getswoopr.com/stocks/indexes/): how indexes are built, weighted and revised. - [Emerging Markets indexes](https://www.getswoopr.com/stocks/indexes/emerging-markets/): others covering the same region. - [Index concentration](https://www.getswoopr.com/technical-analysis/market-concentration/index-concentration/): measuring how much of an index sits in its largest holdings. - [Index rebalancing and inclusion effects](https://www.getswoopr.com/stocks/corporate-actions-catalysts/index-rebalancing-and-inclusion-effects/): what happens to a stock when index membership changes. ## Frequently Asked Questions ### Who maintains the All Share Price Index? Colombo Stock Exchange / S&P DJI maintains the All Share Price Index and publishes the methodology document that defines its eligibility and weighting rules. ### What does the All Share Price Index measure? It measures broad Sri Lankan 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 All Share Price Index constituents? Colombo Stock Exchange / S&P DJI publishes the current constituent list. Swoopr does not republish it, because index providers license constituent data and Swoopr holds no such licence. ## About the author The [Swoopr Editorial Team](https://www.getswoopr.com/authors/swoopr-editorial-team/) writes Swoopr Investment's educational library, covering market structure, analysis methods and the mechanics behind the numbers investors read every day. Our [editorial policy](https://www.getswoopr.com/legal/editorial-policy/) and [corrections policy](https://www.getswoopr.com/legal/corrections-policy/) set out how this content is produced, reviewed and fixed when it is wrong.