Direct Answer
The SPI Extra is a rule-based measurement of Swiss equities that are part of the Swiss Performance Index but not the SMI, covering mid and small-cap segments, maintained by SIX Swiss Exchange. Like every index it owns nothing: it is a number produced by applying a published weighting formula to a selected list of securities, revised on a schedule the provider sets.
What this index covers
The SPI Extra covers Swiss equities that are part of the Swiss Performance Index but not the SMI, covering mid and small-cap segments. SIX Swiss Exchange defines which securities are eligible, how they are selected from that pool, and how much each one contributes to the published number.
The methodology document, published by SIX Swiss Exchange, sets the rules for inclusion and removal. Corporate actions, index reviews, and eligibility changes all move the constituent list on the timetable the provider specifies.
How constituents are weighted
Swoopr has not verified the weighting method for this index against SIX Swiss Exchange's current methodology document, so none is stated here rather than guessed. The provider link below is authoritative.
Current SPI Extra constituents
SIX Swiss Exchange publishes and licenses the SPI Extra 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.
- Europe 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 SPI Extra?
SIX Swiss Exchange maintains the SPI Extra and publishes the methodology document that defines its eligibility and weighting rules.
What does the SPI Extra measure?
It measures Swiss equities that are part of the Swiss Performance Index but not the SMI, covering mid and small-cap segments. The index is a calculated number applying a weighting formula to a selected list of securities, and it holds nothing itself.
Where can I see the current SPI Extra constituents?
SIX Swiss Exchange publishes the current constituent list. Swoopr does not republish it, because index providers license constituent data and Swoopr holds no such licence.