ポルカドット (DOT) トケノミクス

Polkadot’s native token, DOT, serves as the central utility and governance asset for its multichain ecosystem. The network's economic model is designed to balance security, scalability, and community-led growth through a sophisticated set of issuance, allocation, and incentive mechanisms.

Issuance and Inflation Mechanism

Polkadot originally launched with an initial total supply of 1.00 billion DOT. As of April 14, 2024, this supply has increased to approximately 1.43 billion DOT due to the network's inflationary model.

Historically, Polkadot utilized a 10% year-on-year token issuance rate. However, recent governance decisions have shifted the network toward a more disinflationary model. The issuance rate has been adjusted to a fixed amount of 120 million DOT per year. This change ensures that as the total supply grows, the effective inflation rate as a percentage of the total network supply will decrease over time.

The distribution of this newly issued DOT is determined by the network's staking participation:

• Staking Rewards: Approximately 100 million DOT of the annual issuance is earmarked for stakers who provide the backbone of the network's security.
• Treasury Funding: The remaining portion of the annual issuance funds the network treasury.
• Ideal Staking Rate: The specific amount directed to stakers versus the treasury depends on the "system staking rate" relative to an "ideal staking rate." When these rates are equal, all new DOT is rewarded to stakers. If they diverge, a portion is diverted to the treasury. The ideal staking rate typically varies between 45% and 75% depending on the number of active parachain slots.

Allocation and Distribution

The distribution of DOT has evolved from its initial public sale and continues to shift as tokens are unlocked from various programs.

Usage and Incentive Mechanisms

DOT is a multi-purpose utility token with several core functions that drive its demand and ecosystem utility:

Network Security and Staking

Polkadot uses a Nominated Proof-of-Stake (NPoS) consensus mechanism. Users can participate as:

• Validators: Run nodes to verify parachain blocks and participate in consensus. They earn rewards based on "Era Points" (payable actions like issuing validity statements) rather than their total stake.
• Nominators: Tokenholders who stake their DOT to back validator candidates. They receive a pro-rata share of the validator's rewards, minus any commission.

Governance (OpenGov)

DOT is the central tool for Polkadot's on-chain governance. Tokenholders can:

• Propose Changes: Submit proposals for any of the 15 governance tracks. This requires a "submission deposit" of 1 DOT.
• Advance Proposals: Bond "decision deposits" to move proposals to the voting stage.
• Vote: Participate in referenda. Voting weight can be increased through Conviction Voting, where locking DOT for longer periods (up to 896 days) multiplies the voting power by up to 6x.

Resource Allocation (Coretime)

In the Polkadot 2.0 model, the network is moving toward Agile Coretime. This transforms how resources are allocated, allowing for more efficient and scalable access to the Relay Chain's computing power. Previously, this was primarily handled through parachain slot auctions.

Locking and Unlocking Mechanisms

Locking DOT is a fundamental requirement for several network activities, serving as both a security measure and a commitment of resources.

Parachain Slot Auctions and Crowdloans

To secure a dedicated parachain slot, projects must bid DOT in a candle auction.

• Lock Duration: Winning bids result in DOT being locked for the duration of the lease, which is typically 96 weeks.
• Crowdloans: Community members can contribute DOT to a project's bid. If the project wins, the contributors' DOT is locked for the 96-week lease period.
• Unlocking: At the end of the 96-week lease, the DOT is automatically unlocked and returned to the original bidders or crowdloan contributors.

Staking and Governance Unlocking

• Staking Unbonding: DOT staked for security requires an unbonding period before it becomes liquid. As of the 2025 roadmap, the network is working on "Fast Unlocking" to reduce this waiting time and improve user experience.
• Governance Locking: DOT locked for conviction voting is released after the chosen lock period expires, which is calculated in "periods" (e.g., 32 periods equals 896 days).

Deflationary Burn Mechanism

Polkadot includes a burn mechanism to offset inflation. At the end of every 24-day spend period, 1% of the available funds in the network treasury are permanently burned. The treasury is funded by transaction fees, a portion of inflationary rewards, and validator slashing penalties.