I originally heard it in the &quot;Cowspiracy&quot; documentary&quot;.<p>UN and IMF say it&#x27;s around 18-51%:<p><a href="https:&#x2F;&#x2F;youtu.be&#x2F;KpmTiHjUEBU?t=3m27s" rel="nofollow">https:&#x2F;&#x2F;youtu.be&#x2F;KpmTiHjUEBU?t=3m27s</a>