Utilize your financial knowledge, give your answer or opinion to the input question or subject . Answer format is not limited.

How much of each stock do index funds hold?
An index fund is just copying the definition of an index. The group that defines the index determines how to weight the different parts of the index. The index fund just makes sure they invest the same way the index creator wants.  Think of a non-investment scenario. A teacher can grade tests, quizzes, homework, in-class assignments, research papers. They decide how much weight to give each category and how much weight to give each part of each category. when a student wants to see how they are doing they take the information in the syllabus, and generate a few formulas in a spreadsheet to calculate their current grade. They can also calculate what they need to get on the final exam to get the grade they want.