Bitcoin

Crypto & Digital Assets · basic · CC-BY-4.0

Bitcoin (BTC) is the first and largest cryptocurrency by market capitalization, created in 2009 by the pseudonymous Satoshi Nakamoto, operating as a decentralized peer-to-peer payment network secured by a proof-of-work consensus mechanism with a fixed maximum supply of 21 million coins.

Key takeaways

Bitcoin uses a blockchain — a distributed, cryptographically linked chain of transaction records — to maintain a trustless, permissionless ledger without requiring a central authority.
The total supply is algorithmically capped at 21 million BTC; new supply is created through mining, with the issuance rate halving approximately every 4 years (the 'halving') — the last Bitcoin is expected to be mined circa 2140.
Bitcoin's proof-of-work consensus requires miners to solve computationally intensive cryptographic puzzles, making the network highly resistant to 51% attacks at scale but energy-intensive.
Institutionally, Bitcoin is increasingly treated as a store of value and inflation hedge asset class — with publicly traded spot Bitcoin ETFs approved in the U.S. in January 2024 providing direct exposure to institutional and retail investors.
Bitcoin exhibits high volatility (annualized 50–100%), significant tail risk, liquidity constraints in stress events, and regulatory uncertainty — each of which must be incorporated in portfolio risk models.

Explanation

Bitcoin was conceived as a response to the trust failures of the 2008 financial crisis — a system in which two parties could transact directly without relying on a financial intermediary. The Bitcoin whitepaper ('Bitcoin: A Peer-to-Peer Electronic Cash System,' Nakamoto, 2008) described a system using cryptographic proof-of-work to establish consensus on transaction history without any central authority. The genesis block was mined on January 3, 2009, embedding the headline 'Chancellor on brink of second bailout for banks' as a timestamp and a political statement.

The proof-of-work mechanism requires mining nodes to compete to find a nonce that produces a hash of the block header below a target value. The computational difficulty adjusts every 2,016 blocks (approximately 2 weeks) to maintain a 10-minute average block time as mining capacity changes. This difficulty adjustment is what makes Bitcoin's issuance schedule predictable — it will issue exactly 21 million BTC on a pre-programmed schedule regardless of changes in mining participation. The block reward began at 50 BTC and halves every 210,000 blocks: as of 2024, it is 3.125 BTC per block following the April 2024 halving.

From a financial markets perspective, Bitcoin has evolved through several distinct phases. In its first decade it was primarily a retail speculative asset with no institutional infrastructure. From 2017 onward, CME and CBOE introduced Bitcoin futures, providing regulated institutional access. The 2020–2021 bull market saw major corporate treasury allocations (MicroStrategy, Tesla) and the launch of the first North American spot Bitcoin ETFs in Canada. The January 2024 approval of spot Bitcoin ETFs in the United States by the SEC (iShares Bitcoin Trust, Fidelity Wise Origin Bitcoin Fund, etc.) represented a watershed moment, bringing exchange-listed, tax-efficient Bitcoin exposure to retail and institutional investors alike and generating $10+ billion in net inflows in the first weeks.

For institutional portfolio construction, Bitcoin's role is most often framed as: (1) an inflation hedge or store-of-value alternative to gold; (2) a uncorrelated risk asset in moderation (correlations with equities are low in normal environments but spike in liquidity crises); or (3) a high-risk speculative allocation for return enhancement. Academic and practitioner research suggests that a 1–5% allocation to Bitcoin in a diversified portfolio has historically improved the Sharpe ratio of the overall portfolio, driven by the combination of high expected return and low correlation with traditional assets — though future performance cannot be extrapolated from past bull market conditions.

Example

In 2020, MicroStrategy Inc. adopted Bitcoin as its primary treasury reserve asset, purchasing approximately 21,454 BTC at an average price of $15,964 per coin (total cost approximately $342 million). By late 2024, Bitcoin trading above $90,000 per coin, MicroStrategy's Bitcoin holdings were worth approximately $19+ billion — a gain of over 50x on the initial investment. The strategy significantly outperformed cash alternatives but subjected MicroStrategy's balance sheet to extreme volatility: during the 2022 bear market, Bitcoin fell below $20,000, bringing the holdings to near breakeven on a mark-to-market basis and triggering margin call concerns on BTC-collateralized debt that the company had used to finance additional purchases. This example illustrates both the extraordinary return potential and the leverage-amplified risk profile of Bitcoin as a treasury asset.

Bitcoin

Key takeaways

Explanation

Example

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