It depends on the index! “Equal weight in the largest five banks in Lithuania” is an index. “500 large American companies chosen from a list of candidates by a selection committee in NYCt” is an index. “Every company on the Tokyo Stock Exchange” is an index.
It depends on the index! “Equal weight in the largest five banks in Lithuania” is an index. “500 large American companies chosen from a list of candidates by a selection committee in NYCt” is an index. “Every company on the Tokyo Stock Exchange” is an index.