What the Number Is, and What It Is Not

Where the number comes from

There is no exchange in the sense of a single venue. Bitcoin trades on many, each with its own
order book, and every price you see is an aggregate across some selection of them, weighted by
volume or by some editorial choice the aggregator made.

This is why sites disagree slightly and occasionally more than slightly. A venue with
restricted withdrawals can trade at a persistent premium, because coins inside it cannot leave;
including that venue pulls the average up without anything real having changed.

What market capitalisation measures

Circulating supply multiplied by the last traded price. That is the whole calculation. It is
not the amount of money that has entered the asset, and it is not the amount that could be extracted by selling, because a large sell order would move the price long before it reached that
figure.

For bitcoin the number is at least computed from a deep and widely traded market, which makes
it more meaningful than the same figure for a thin asset. It is still a multiplication rather
than a measurement, and headlines comparing it to national economies are comparing two
different kinds of quantity.

The halving argument

Issuance halves on a fixed schedule, and the price has historically risen in the period
afterwards. The counter-argument is straightforward: the schedule has been public since
2009, so a market that prices known information should have reflected it already.

Both positions are held by serious people, and the sample size is four events. That is not
enough to settle it, which is the honest conclusion and the one least often stated. Treat
confident claims in either direction as claims about the speaker rather than about the asset.

The metrics people quote, and what they rest on

Exchange balances are inferred from addresses believed to belong to a platform, and the
attribution is pattern analysis rather than confirmation. Realised capitalisation values coins
at the price they last moved, which is a genuinely different and more useful number. Long-term
holder supply depends on a threshold somebody chose.

Each is more informative than the raw price and none is a measurement in the way it is
presented. Knowing which assumption sits underneath a chart is the difference between using it
and being persuaded by it.

The two prices that are not the spot price

Most figures quoted in coverage are the spot price, and two others move alongside it while
being routinely mixed into the same sentence. Futures trade at a price for settlement later,
and the gap between that and spot is a cost of carry rather than a forecast, even though it is
often read as one.

Perpetual contracts have no settlement date and hold themselves near spot through a periodic
payment between the two sides. When the payment is running strongly in one direction it says
something concrete: positions on that side are crowded enough to be paying to stay open. That
is a genuine market-structure reading and it is one of the few figures in this area that
measures a fact rather than an opinion.

Where it goes wrong is treating either as a prediction. A futures curve is not the market’s
view of next year’s price; it is mostly the cost of financing a position until then. Reading it
as a forecast produces confident statements about the future built on what is essentially an
interest rate.

Why the price is quoted in a currency at all

Because that is what people buy it with, and it produces a permanent framing effect: the asset
is always presented as a quantity of currency rather than the reverse. A rise is described as
the asset appreciating rather than the currency depreciating against it, and both descriptions
fit the same data.

This is not a semantic game. Which side of that framing you adopt determines whether a
declining price reads as a loss or as a change in the exchange rate between two things you
hold views on, and the framing is doing more work in most analysis than the numbers are.