Companies that joined or left an index, newest first. Derived by comparing consecutive lists from the funds that track it, so each change is dated to the window between two reports (previousAsOfDate to observedAsOfDate) rather than to an announcement. Records from several funds for the same company and direction over overlapping windows are collapsed into one event, keeping the narrowest window.

What happened to a requested ticker that no longer trades. "delisted": the company has no current US listing, so the answer is its history. "renamed": the company now trades as successorTicker, its current US presentation ticker (possibly another share class). A listed series (short volume, short interest, off-exchange volume, fails-to-deliver, congressional trades) is the retired ticker's own; a company-level read is the company's data.