Bitcoin Q&A: What are "bitcoin days destroyed"?

What are "bitcoin days destroyed," how is it calculated, and what is the significance of this maturity figure?

This question was part of the (late) August monthly live Patreon Q&A session, which took place on September 1st 2018. If you want early-access to talks and a chance to participate in the monthly live Q&As with Andreas, become a patron: https://www.patreon.com/aantonop

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Andreas M. Antonopoulos is a technologist and serial entrepreneur who has become one of the most well-known and respected figures in bitcoin.

Follow on Twitter: @aantonop https://twitter.com/aantonop
Website: https://antonopoulos.com/

He is the author of two books: “Mastering Bitcoin,” published by O’Reilly Media and considered the best technical guide to bitcoin; “The Internet of Money,” a book about why bitcoin matters.

THE INTERNET OF MONEY, v1: https://www.amazon.co.uk/Internet-Money-collection-Andreas-Antonopoulos/dp/1537000454/ref=asap_bc?ie=UTF8

[NEW] THE INTERNET OF MONEY, v2: https://www.amazon.com/Internet-Money-Andreas-M-Antonopoulos/dp/194791006X/ref=asap_bc?ie=UTF8

MASTERING BITCOIN: https://www.amazon.co.uk/Mastering-Bitcoin-Unlocking-Digital-Cryptocurrencies/dp/1449374042

[NEW] MASTERING BITCOIN, 2nd Edition: https://www.amazon.com/Mastering-Bitcoin-Programming-Open-Blockchain/dp/1491954388

Translations of MASTERING BITCOIN: https://bitcoinbook.info/translations-of-mastering-bitcoin/

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