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Glossary · Audience & measurement

Audience concentration

Also: Herfindahl–Hirschman index, HHI

Definition

Audience concentration: How evenly a following is spread across accounts: the sum of each account's squared share of total followers, known as the Herfindahl–Hirschman index.

What it means

Audience concentration borrows the Herfindahl–Hirschman index (HHI) from competition economics, where it measures how concentrated a market is by squaring each firm's market share and adding the results1. Applied to an audience, each share is one account's followers as a fraction of the total across all measured accounts.

With shares written as fractions, the index runs from near 0, a following spread thinly across many accounts, to 1, a following that sits on one. Squaring gives large shares far more weight than small ones, so one dominant account keeps the index high however many minor accounts sit beside it. Competition authorities write shares as percentages, which puts the same index on a scale up to 10,0001.

Example

Illustratively, a creator with 70% of their followers on Instagram, 20% on YouTube and 10% on Telegram has a concentration of 0.49 + 0.04 + 0.01 = 0.54. The same total split 40%, 30% and 30% gives 0.16 + 0.09 + 0.09 = 0.34.

Why it matters to an IB

A following concentrated on one platform is one suspension or policy change away from unreachable, and so is an IB business built on it. Two creators with the same total reach can carry very different risk; the index shows which. See how to read a trading audience honestly.

Sources

First-party figures are Gravity's own observations of its product. External sources were read on the date shown.

  1. Herfindahl-Hirschman Index — U.S. Department of Justice, Antitrust Division

    Regulator · read 28 September 2026

In the Journal

Where “Audience concentration” comes up

  1. 01

    Marketing & advertisingHow-to9 min read

    A social content plan for introducing brokers

    Followers come to trust an IB who teaches, shows only what they can back and says who pays them. A weekly plan built on that, in the audience's language, at a pace you can keep.

  2. 02

    Marketing & advertisingGuide10 min read

    Forex IB marketing: how introducing brokers win and keep clients

    An IB's marketing is one system, not a feed: attention, trust, a disclosed link and a reason to stay. What each channel does, what advertising may do, and where the rules draw the line.

  3. 03

    Audience & measurementHow-to8 min read

    How to judge a sub-IB's audience before you sign them

    A sub-IB brings you their audience and their habits with it. Nine checks to run before you agree terms, from the follower count to what they promise the people who follow them.

  4. 04

    Audience & measurementGuide9 min read

    How to read a trading audience honestly

    Follower counts are the vanity figure. What an IB needs before choosing a partner is how engaged an audience is, where it sits, and what nobody has measured yet.

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