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Publications
  • July 2024
  • Article
  • Journal of Financial Economics

The Passive-Ownership Share Is Double What You Think It Is

By: Alex Chinco and Marco Sammon
  • Format:Print
  • | Pages:22
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Abstract

Each time a stock gets added to or dropped from a benchmark index, we ask: “How much money would have to be tracking that index to explain the huge spike in rebalancing volume we observe on reconstitution day?” While index funds held 16% of the US stock market in 2021, we put the true passive-ownership share at 33.3%. Our headline number is twice as large because it reflects index funds as well as other kinds of passive investors, such as direct indexers and active managers who are closet indexing.

Keywords

Indexing; Passive Investing; Exchange-traded Funds (ETFs); Russell Reconstitution Day; Trading Volume; Information-based Asset Pricing; Investment Funds; Asset Pricing

Citation

Chinco, Alex, and Marco Sammon. "The Passive-Ownership Share Is Double What You Think It Is." Journal of Financial Economics 157 (July 2024).
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About The Author

Marco Sammon

Finance
→More Publications

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    Index Rebalancing and Stock Market Composition: Do Indexes Time the Market?

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    First Citizens’ Acquisition of SVB

    By: Samuel Antill, Marco Sammon and Erik Stafford
    • April 2025
    • Journal of Finance

    The Disappearing Index Effect

    By: Robin Greenwood and Marco Sammon
More from the Authors
  • Index Rebalancing and Stock Market Composition: Do Indexes Time the Market? By: Marco Sammon and John J. Shim
  • First Citizens’ Acquisition of SVB By: Samuel Antill, Marco Sammon and Erik Stafford
  • The Disappearing Index Effect By: Robin Greenwood and Marco Sammon
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