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Sat, 09 Jul 2022 07:26:24 -0700 (PDT) Content-Type: multipart/alternative; boundary=Apple-Mail-0A63F663-FFB5-4325-A4DD-CA9261D0E08C Content-Transfer-Encoding: 7bit From: Eric Voskuil <eric@voskuil.org> Mime-Version: 1.0 (1.0) Date: Sat, 9 Jul 2022 07:26:22 -0700 Message-Id: <ABA1D62F-C22C-413C-8710-72521D4D8B21@voskuil.org> References: <Ysl4t9K8lfxRSsNM@petertodd.org> In-Reply-To: <Ysl4t9K8lfxRSsNM@petertodd.org> To: Peter Todd <pete@petertodd.org>, Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org> X-Mailer: iPhone Mail (19F77) Subject: Re: [bitcoin-dev] Surprisingly, Tail Emission Is Not Inflationary X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Bitcoin Protocol Discussion <bitcoin-dev.lists.linuxfoundation.org> List-Unsubscribe: <https://lists.linuxfoundation.org/mailman/options/bitcoin-dev>, <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=unsubscribe> List-Archive: <http://lists.linuxfoundation.org/pipermail/bitcoin-dev/> List-Post: <mailto:bitcoin-dev@lists.linuxfoundation.org> List-Help: <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=help> List-Subscribe: <https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev>, <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=subscribe> X-List-Received-Date: Sat, 09 Jul 2022 14:26:29 -0000 --Apple-Mail-0A63F663-FFB5-4325-A4DD-CA9261D0E08C Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable > Due to lost coins, a tail emission/fixed reward actually results in a stab= le money supply. Not an (monetarily) inflationary supply. This observation is not a proof of lost coins, that is an assumption. It is t= he provable consequence of market, as opposed to monopoly, production. https://github.com/libbitcoin/libbitcoin-system/wiki/Inflation-Principle Mises=E2=80=99 unfortunate error in the application of the Cantillon Effect t= o gold perpetuates this misperception. One could imagine applying this theor= y to all goods, not just money, and conclude perpetual loss of value in ever= ything produced, as a consequence of production. One might then be tempted t= o attribute the fact that this is not observable to loss/depreciation/consum= ption. While it is certainly possible that the amount of gold produced every= year is offset by the amount lost, this of course implies that all of it is= lost. =E2=80=9CCirculation=E2=80=9D does not determine demand, all money is always= held by someone. Changing hands only changes who owns the money, not its pu= rchasing power. See Rothbard=E2=80=99s critique of monetary =E2=80=9Cvelocit= y=E2=80=9D. e > On Jul 9, 2022, at 05:47, Peter Todd via bitcoin-dev <bitcoin-dev@lists.li= nuxfoundation.org> wrote: >=20 > =EF=BB=BFNew blog post: >=20 > https://petertodd.org/2022/surprisingly-tail-emission-is-not-inflationary >=20 > tl;dr: Due to lost coins, a tail emission/fixed reward actually results in= a > stable money supply. Not an (monetarily) inflationary supply. >=20 > ...and for the purposes of reply/discussion, attached is the article itsel= f in > markdown format: >=20 > --- > layout: post > title: "Surprisingly, Tail Emission Is Not Inflationary" > date: 2022-07-09 > tags: > - bitcoin > - monero > --- >=20 > At present, all notable proof-of-work currencies reward miners with both a= block > reward, and transaction fees. With most currencies (including Bitcoin) pha= sing > out block rewards over time. However in no currency have transaction fees > consistently been more than 5% to 10% of the total mining > reward[^fee-in-reward], with the exception of Ethereum, from June 2020 to A= ug 2021. > To date no proof-of-work currency has ever operated solely on transaction > fees[^pow-tweet], and academic analysis has found that in this condition b= lock > generation is unstable.[^instability-without-block-reward] To paraphrase A= ndrew > Poelstra, it's a scary phase change that no other coin has gone through.[^= apoelstra-quote] >=20 > [^pow-tweet]: [I asked on Twitter](https://twitter.com/peterktodd/status/1= 543231264597090304) and no-one replied with counter-examples. >=20 > [^fee-in-reward]: [Average Fee Percentage in Total Block Reward](https://b= itinfocharts.com/comparison/fee_to_reward-btc-eth-bch-ltc-doge-xmr-bsv-dash-= zec.html#alltime) >=20 > [^instability-without-block-reward]: [On the Instability of Bitcoin Withou= t the Block Reward](https://www.cs.princeton.edu/~arvindn/publications/minin= g_CCS.pdf) >=20 > [^apoelstra-quote]: [=46rom a panel at TABConf 2021](https://twitter.com/p= eterktodd/status/1457066946898317316) >=20 > Monero has chosen to implement what they call [tail > emission](https://www.getmonero.org/resources/moneropedia/tail-emission.ht= ml): > a fixed reward per block that continues indefinitely. Dogecoin also has a f= ixed > reward, which they widely - and incorrectly - refer to as an "abundant" su= pply[^dogecoin-abundant]. >=20 > [^dogecoin-abundant]: Googling "dogecoin abundant" returns dozens of hits.= >=20 > This article will show that a fixed block reward does **not** lead to an > abundant supply. In fact, due to the inevitability of lost coins, a fixed > reward converges to a **stable** monetary supply that is neither inflation= ary > nor deflationary, with the total supply proportional to rate of tail emiss= ion > and probability of coin loss. >=20 > Credit where credit is due: after writing the bulk of this article I found= out > that Monero developer [smooth_xmr](https://www.reddit.com/user/smooth_xmr/= ) > also observed that tail emission results in a stable coin supply > [a few years ago](https://www.reddit.com/r/Monero/comments/4z0azk/maam_28_= monero_ask_anything_monday/d6sixyi/). > There's probably others too: it's a pretty obvious result. >=20 >=20 > <div markdown=3D"1" class=3D"post-toc"> > # Contents > {:.no_toc} > 0. TOC > {:toc} > </div> >=20 > ## Modeling the Fixed-Reward Monetary Supply >=20 > Since the number of blocks is large, we can model the monetary supply as a= > continuous function $$N(t)$$, where $$t$$ is a given moment in time. If th= e > block reward is fixed we can model the reward as a slope $$k$$ added to an= > initial supply $$N_0$$: >=20 > $$ > N(t) =3D N_0 + kt > $$ >=20 > Of course, this isn't realistic as coins are constantly being lost due to > deaths, forgotten passphrases, boating accidents, etc. These losses are > independent: I'm not any more or less likely to forget my passphrase becau= se > you recently lost your coins in a boating accident =E2=80=94 an accident I= probably > don't even know happened. Since the number of individual coins (and their > owners) is large =E2=80=94 as with the number of blocks =E2=80=94 we can m= odel this loss as > though it happens continuously. >=20 > Since coins can only be lost once, the *rate* of coin loss at time $$t$$ i= s > proportional to the total supply *at that moment* in time. So let's look a= t the > *first derivative* of our fixed-reward coin supply: >=20 > $$ > \frac{dN(t)}{dt} =3D k > $$ >=20 > ...and subtract from it the lost coins, using $$\lambda$$ as our [coin los= s > constant](https://en.wikipedia.org/wiki/Exponential_decay): >=20 > $$ > \frac{dN(t)}{dt} =3D k - \lambda N(t) > $$ >=20 > That's a first-order differential equation, which can be easily solved wit= h > separation of variables to get: >=20 > $$ > N(t) =3D \frac{k}{\lambda} - Ce^{-\lambda t} > $$ >=20 > To remove the integration constant $$C$$, let's look at $$t =3D 0$$, where= the > coin supply is $$N_0$$: >=20 > $$ > \begin{align} > N_0 &=3D \frac{k}{\lambda} - Ce^{-\lambda 0} =3D \frac{k}{\lambda} - C \= \ > C &=3D \frac{k}{\lambda} - N_0 > \end{align} > $$ >=20 > Thus: >=20 > $$ > \begin{align} > N(t) &=3D \frac{k}{\lambda} - \left(\frac{k}{\lambda} - N_0 \right)e^{-= \lambda t} \\ > &=3D \frac{k}{\lambda} + \left(N_0 - \frac{k}{\lambda} \right)e^{-= \lambda t} > \end{align} > $$ >=20 >=20 > ## Long Term Coin Supply >=20 > It's easy to see that in the long run, the second half of the coin supply > equation goes to zero because $$\lim_{t \to \infty} e^{-\lambda t} =3D 0$$= : >=20 > $$ > \begin{align} > \lim_{t \to \infty} N(t) &=3D \lim_{t \to \infty} \left[ \frac{k}{\lamb= da} + \left(N_0 - \frac{k}{\lambda} \right)e^{-\lambda t} \right ] =3D \frac= {k}{\lambda} \\ > N(\infty) &=3D \frac{k}{\lambda} > \end{align} > $$ >=20 > An intuitive explanation for this result is that in the long run, the init= ial > supply $$N_0$$ doesn't matter, because approximately all of those coins wi= ll > eventually be lost. Thus in the long run, the coin supply will converge to= wards > $$\frac{k}{\lambda}$$, the point where coins are created just as fast as t= hey > are lost. >=20 >=20 > ## Short Term Dynamics and Economic Considerations >=20 > Of course, the intuitive explanation for why supply converges to > $$\frac{k}{\lambda}$$, also tells us that supply must converge fairly slow= ly: > if 1% of something is lost per year, after 100 years 37% of the initial su= pply > remains. It's not clear what the rate of lost coins actually is in a matur= e, > valuable, coin. But 1%/year is likely to be a good guess =E2=80=94 quite p= ossibly less. >=20 > In the case of Monero, they've introduced tail emission at a point where i= t > represents a 0.9% apparent monetary inflation rate[^p2pool-tail]. Since th= e number of > previously lost coins, and the current rate of coin loss, is > unknown[^unknowable] it's not possible to know exactly what the true monet= ary > inflation rate is right now. But regardless, the rate will only converge > towards zero going forward. >=20 > [^unknowable]: Being a privacy coin with [shielded amounts](https://localm= onero.co/blocks/richlist), it's not even possible to get an estimate of the t= otal amount of XMR in active circulation. >=20 > [^p2pool-tail]: P2Pool operates [a page with real-time date figures](https= ://p2pool.io/tail.html). >=20 > If an existing coin decides to implement tail emission as a means to fund > security, choosing an appropriate emission rate is simple: decide on the > maximum amount of inflation you are willing to have in the worst case, and= set > the tail emission accordingly. In reality monetary inflation will be even l= ower > on day zero due to lost coins, and in the long run, it will converge towar= ds > zero. >=20 > The fact is, economic volatility dwarfs the effect of small amounts of > inflation. Even a 0.5% inflation rate over 50 years only leads to a 22% dr= op. > Meanwhile at the time of writing, Bitcoin has dropped 36% in the past year= , and > gained 993% over the past 5 years. While this discussion is a nice excuse t= o > use some mildly interesting math, in the end it's totally pedantic. >=20 > ## Could Bitcoin Add Tail Emission? >=20 > ...and why could Monero? >=20 > Adding tail emission to Bitcoin would be a hard fork: a incompatible rule > change that existing Bitcoin nodes would reject as invalid. While Monero w= as > able to get sufficiently broad consensus in the community to implement tai= l > emission, it's unclear at best if it would ever be possible to achieve tha= t for > the much larger[^btc-vs-xmr-market-cap] Bitcoin. Additionally, Monero has a= > culture of frequent hard forks that simply does not exist in Bitcoin. >=20 > [^btc-vs-xmr-market-cap]: [As of writing](https://web.archive.org/web/2022= 0708143920/https://www.coingecko.com/), the apparent market cap of Bitcoin i= s $409 billion, almost 200x larger than Monero's $2.3 billion. >=20 > Ultimately, as long as a substantial fraction of the Bitcoin community con= tinue > to run full nodes, the only way tail emission could ever be added to Bitco= in is > by convincing that same community that it is a good idea. >=20 >=20 > ## Footnotes > _______________________________________________ > bitcoin-dev mailing list > bitcoin-dev@lists.linuxfoundation.org > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev --Apple-Mail-0A63F663-FFB5-4325-A4DD-CA9261D0E08C Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable <html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D= utf-8"></head><body dir=3D"auto"><div dir=3D"ltr"></div><div dir=3D"ltr"><fo= nt color=3D"#000000"><span style=3D"caret-color: rgb(255, 255, 255); -webkit= -text-size-adjust: auto;">> </span></font>Due to lost coins, a tail e= mission/fixed reward actually results in a stable money supply. Not an (mone= tarily) inflationary supply.</div><div dir=3D"ltr"><font color=3D"#000000"><= span style=3D"caret-color: rgb(255, 255, 255); -webkit-text-size-adjust: aut= o;"><br></span></font></div><div dir=3D"ltr"><font color=3D"#000000"><span s= tyle=3D"caret-color: rgb(255, 255, 255); -webkit-text-size-adjust: auto;">Th= is observation is not a proof of lost coins, that is an assumption. It is th= e provable consequence of market, as opposed to monopoly, production.<br></s= pan></font><div style=3D"caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><f= ont color=3D"#000000"><span style=3D"caret-color: rgb(255, 255, 255); -webki= t-text-size-adjust: auto;"><br></span></font></div><div style=3D"caret-color= : rgb(0, 0, 0); color: rgb(0, 0, 0);"><a href=3D"https://github.com/libbitco= in/libbitcoin-system/wiki/Inflation-Principle">https://github.com/libbitcoin= /libbitcoin-system/wiki/Inflation-Principle</a><div dir=3D"ltr"><br></div><d= iv dir=3D"ltr">Mises=E2=80=99 unfortunate error in the application of the Ca= ntillon Effect to gold perpetuates this misperception. One could imagine app= lying this theory to all goods, not just money, and conclude perpetual loss o= f value in everything produced, as a consequence of production. One might th= en be tempted to attribute the fact that this is not observable to loss/depr= eciation/consumption. While it is certainly possible that the amount of gold= produced every year is offset by the amount lost, this of course implies th= at all of it is lost.</div><div dir=3D"ltr"><br></div><div dir=3D"ltr">=E2=80= =9CCirculation=E2=80=9D does not determine demand, all money is always held b= y someone. Changing hands only changes who owns the money, not its purchasin= g power. See Rothbard=E2=80=99s critique of monetary =E2=80=9Cvelocity=E2=80= =9D.</div><div dir=3D"ltr"><br></div><div dir=3D"ltr">e</div></div></div><di= v dir=3D"ltr"><br><blockquote type=3D"cite">On Jul 9, 2022, at 05:47, Peter T= odd via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> wrote:<br>= <br></blockquote></div><blockquote type=3D"cite"><div dir=3D"ltr">=EF=BB=BF<= span>New blog post:</span><br><span></span><br><span>https://petertodd.org/2= 022/surprisingly-tail-emission-is-not-inflationary</span><br><span></span><b= r><span>tl;dr: Due to lost coins, a tail emission/fixed reward actually resu= lts in a</span><br><span>stable money supply. Not an (monetarily) inflationa= ry supply.</span><br><span></span><br><span>...and for the purposes of reply= /discussion, attached is the article itself in</span><br><span>markdown form= at:</span><br><span></span><br><span>---</span><br><span>layout: post</span>= <br><span>title: "Surprisingly, Tail Emission Is Not Inflationary"</sp= an><br><span>date: 2022-07-09</span><br><span>tags:</span><br><s= pan>- bitcoin</span><br><span>- monero</span><br><span>---</span><br><span><= /span><br><span>At present, all notable proof-of-work currencies reward mine= rs with both a block</span><br><span>reward, and transaction fees. With most= currencies (including Bitcoin) phasing</span><br><span>out block rewards ov= er time. However in no currency have transaction fees</span><br><span>consis= tently been more than 5% to 10% of the total mining</span><br><span>reward[^= fee-in-reward], with the exception of Ethereum, from June 2020 to Aug 2021.<= /span><br><span>To date no proof-of-work currency has ever operated solely o= n transaction</span><br><span>fees[^pow-tweet], and academic analysis has fo= und that in this condition block</span><br><span>generation is unstable.[^in= stability-without-block-reward] To paraphrase Andrew</span><br><span>Poelstr= a, it's a scary phase change that no other coin has gone through.[^apoelstra= -quote]</span><br><span></span><br><span>[^pow-tweet]: [I asked on Twitter](= https://twitter.com/peterktodd/status/1543231264597090304) and no-one replie= d with counter-examples.</span><br><span></span><br><span>[^fee-in-reward]: [= Average Fee Percentage in Total Block Reward](https://bitinfocharts.com/comp= arison/fee_to_reward-btc-eth-bch-ltc-doge-xmr-bsv-dash-zec.html#alltime)</sp= an><br><span></span><br><span>[^instability-without-block-reward]: [On the I= nstability of Bitcoin Without the Block Reward](https://www.cs.princeton.edu= /~arvindn/publications/mining_CCS.pdf)</span><br><span></span><br><span>[^ap= oelstra-quote]: [=46rom a panel at TABConf 2021](https://twitter.com/peterkt= odd/status/1457066946898317316)</span><br><span></span><br><span>Monero has c= hosen to implement what they call [tail</span><br><span>emission](https://ww= w.getmonero.org/resources/moneropedia/tail-emission.html):</span><br><span>a= fixed reward per block that continues indefinitely. Dogecoin also has a fix= ed</span><br><span>reward, which they widely - and incorrectly - refer to as= an "abundant" supply[^dogecoin-abundant].</span><br><span></span><br><span>= [^dogecoin-abundant]: Googling "dogecoin abundant" returns dozens of hits.</= span><br><span></span><br><span>This article will show that a fixed block re= ward does **not** lead to an</span><br><span>abundant supply. In fact, due t= o the inevitability of lost coins, a fixed</span><br><span>reward converges t= o a **stable** monetary supply that is neither inflationary</span><br><span>= nor deflationary, with the total supply proportional to rate of tail emissio= n</span><br><span>and probability of coin loss.</span><br><span></span><br><= span>Credit where credit is due: after writing the bulk of this article I fo= und out</span><br><span>that Monero developer [smooth_xmr](https://www.reddi= t.com/user/smooth_xmr/)</span><br><span>also observed that tail emission res= ults in a stable coin supply</span><br><span>[a few years ago](https://www.r= eddit.com/r/Monero/comments/4z0azk/maam_28_monero_ask_anything_monday/d6sixy= i/).</span><br><span>There's probably others too: it's a pretty obvious resu= lt.</span><br><span></span><br><span></span><br><span><div markdown=3D"1"= class=3D"post-toc"></span><br><span># Contents</span><br><span>{:.no_toc= }</span><br><span>0. TOC</span><br><span>{:toc}</span><br><span></div>= </span><br><span></span><br><span>## Modeling the Fixed-Reward Monetary Supp= ly</span><br><span></span><br><span>Since the number of blocks is large, we c= an model the monetary supply as a</span><br><span>continuous function $$N(t)= $$, where $$t$$ is a given moment in time. If the</span><br><span>block rewa= rd is fixed we can model the reward as a slope $$k$$ added to an</span><br><= span>initial supply $$N_0$$:</span><br><span></span><br><span>$$</span><br><= span>N(t) =3D N_0 + kt</span><br><span>$$</span><br><span></span><br><span>O= f course, this isn't realistic as coins are constantly being lost due to</sp= an><br><span>deaths, forgotten passphrases, boating accidents, etc. These lo= sses are</span><br><span>independent: I'm not any more or less likely to for= get my passphrase because</span><br><span>you recently lost your coins in a b= oating accident =E2=80=94 an accident I probably</span><br><span>don't even k= now happened. Since the number of individual coins (and their</span><br><spa= n>owners) is large =E2=80=94 as with the number of blocks =E2=80=94 we can m= odel this loss as</span><br><span>though it happens continuously.</span><br>= <span></span><br><span>Since coins can only be lost once, the *rate* of coin= loss at time $$t$$ is</span><br><span>proportional to the total supply *at t= hat moment* in time. So let's look at the</span><br><span>*first derivative*= of our fixed-reward coin supply:</span><br><span></span><br><span>$$</span>= <br><span>\frac{dN(t)}{dt} =3D k</span><br><span>$$</span><br><span></span><= br><span>...and subtract from it the lost coins, using $$\lambda$$ as our [c= oin loss</span><br><span>constant](https://en.wikipedia.org/wiki/Exponential= _decay):</span><br><span></span><br><span>$$</span><br><span>\frac{dN(t)}{dt= } =3D k - \lambda N(t)</span><br><span>$$</span><br><span></span><br><span>T= hat's a first-order differential equation, which can be easily solved with</= span><br><span>separation of variables to get:</span><br><span></span><br><s= pan>$$</span><br><span>N(t) =3D \frac{k}{\lambda} - Ce^{-\lambda t}</span><b= r><span>$$</span><br><span></span><br><span>To remove the integration consta= nt $$C$$, let's look at $$t =3D 0$$, where the</span><br><span>coin supply i= s $$N_0$$:</span><br><span></span><br><span>$$</span><br><span>\begin{align}= </span><br><span> N_0 &=3D \frac{k}{\lambda} - Ce^{-\l= ambda 0} =3D \frac{k}{\lambda} - C \\</span><br><span> &nb= sp; C &=3D \frac{k}{\lambda} - N_0</span><br><span>\end{align}</spa= n><br><span>$$</span><br><span></span><br><span>Thus:</span><br><span></span= ><br><span>$$</span><br><span>\begin{align}</span><br><span> &nb= sp;N(t) &=3D \frac{k}{\lambda} - \left(\frac{k}{\lambda} - N_0 \right)e^= {-\lambda t} \\</span><br><span> &= nbsp;&=3D \frac{k}{\lambda} + \left(N_0 - \frac{k}{\lambda} \right)e^{-\= lambda t}</span><br><span>\end{align}</span><br><span>$$</span><br><span></s= pan><br><span></span><br><span>## Long Term Coin Supply</span><br><span></sp= an><br><span>It's easy to see that in the long run, the second half of the c= oin supply</span><br><span>equation goes to zero because $$\lim_{t \to \inft= y} e^{-\lambda t} =3D 0$$:</span><br><span></span><br><span>$$</span><br><sp= an>\begin{align}</span><br><span> \lim_{t \to \infty} N(t)= &=3D \lim_{t \to \infty} \left[ \frac{k}{\lambda} + \left(N_0 - \frac{k= }{\lambda} \right)e^{-\lambda t} \right ] =3D \frac{k}{\lambda} \\</span><br= ><span> &n= bsp; N(\infty) &=3D \frac{k}{\lambda}= </span><br><span>\end{align}</span><br><span>$$</span><br><span></span><br><= span>An intuitive explanation for this result is that in the long run, the i= nitial</span><br><span>supply $$N_0$$ doesn't matter, because approximately a= ll of those coins will</span><br><span>eventually be lost. Thus in the long r= un, the coin supply will converge towards</span><br><span>$$\frac{k}{\lambda= }$$, the point where coins are created just as fast as they</span><br><span>= are lost.</span><br><span></span><br><span></span><br><span>## Short Term Dy= namics and Economic Considerations</span><br><span></span><br><span>Of cours= e, the intuitive explanation for why supply converges to</span><br><span>$$\= frac{k}{\lambda}$$, also tells us that supply must converge fairly slowly:</= span><br><span>if 1% of something is lost per year, after 100 years 37% of t= he initial supply</span><br><span>remains. It's not clear what the rate of l= ost coins actually is in a mature,</span><br><span>valuable, coin. But 1%/ye= ar is likely to be a good guess =E2=80=94 quite possibly less.</span><br><sp= an></span><br><span>In the case of Monero, they've introduced tail emission a= t a point where it</span><br><span>represents a 0.9% apparent monetary infla= tion rate[^p2pool-tail]. Since the number of</span><br><span>previously lost= coins, and the current rate of coin loss, is</span><br><span>unknown[^unkno= wable] it's not possible to know exactly what the true monetary</span><br><s= pan>inflation rate is right now. But regardless, the rate will only converge= </span><br><span>towards zero going forward.</span><br><span></span><br><spa= n>[^unknowable]: Being a privacy coin with [shielded amounts](https://localm= onero.co/blocks/richlist), it's not even possible to get an estimate of the t= otal amount of XMR in active circulation.</span><br><span></span><br><span>[= ^p2pool-tail]: P2Pool operates [a page with real-time date figures](https://= p2pool.io/tail.html).</span><br><span></span><br><span>If an existing coin d= ecides to implement tail emission as a means to fund</span><br><span>securit= y, choosing an appropriate emission rate is simple: decide on the</span><br>= <span>maximum amount of inflation you are willing to have in the worst case,= and set</span><br><span>the tail emission accordingly. In reality monetary i= nflation will be even lower</span><br><span>on day zero due to lost coins, a= nd in the long run, it will converge towards</span><br><span>zero.</span><br= ><span></span><br><span>The fact is, economic volatility dwarfs the effect o= f small amounts of</span><br><span>inflation. Even a 0.5% inflation rate ove= r 50 years only leads to a 22% drop.</span><br><span>Meanwhile at the time o= f writing, Bitcoin has dropped 36% in the past year, and</span><br><span>gai= ned 993% over the past 5 years. While this discussion is a nice excuse to</s= pan><br><span>use some mildly interesting math, in the end it's totally peda= ntic.</span><br><span></span><br><span>## Could Bitcoin Add Tail Emission?</= span><br><span></span><br><span>...and why could Monero?</span><br><span></s= pan><br><span>Adding tail emission to Bitcoin would be a hard fork: a incomp= atible rule</span><br><span>change that existing Bitcoin nodes would reject a= s invalid. While Monero was</span><br><span>able to get sufficiently broad c= onsensus in the community to implement tail</span><br><span>emission, it's u= nclear at best if it would ever be possible to achieve that for</span><br><s= pan>the much larger[^btc-vs-xmr-market-cap] Bitcoin. Additionally, Monero ha= s a</span><br><span>culture of frequent hard forks that simply does not exis= t in Bitcoin.</span><br><span></span><br><span>[^btc-vs-xmr-market-cap]: [As= of writing](https://web.archive.org/web/20220708143920/https://www.coingeck= o.com/), the apparent market cap of Bitcoin is $409 billion, almost 200x lar= ger than Monero's $2.3 billion.</span><br><span></span><br><span>Ultimately,= as long as a substantial fraction of the Bitcoin community continue</span><= br><span>to run full nodes, the only way tail emission could ever be added t= o Bitcoin is</span><br><span>by convincing that same community that it is a g= ood idea.</span><br><span></span><br><span></span><br><span>## Footnotes</sp= an><br><span>_______________________________________________</span><br><span= >bitcoin-dev mailing list</span><br><span>bitcoin-dev@lists.linuxfoundation.= org</span><br><span>https://lists.linuxfoundation.org/mailman/listinfo/bitco= in-dev</span><br><div><signature.asc></div></div></blockquote></body><= /html>= --Apple-Mail-0A63F663-FFB5-4325-A4DD-CA9261D0E08C--