We have been asked about the index and we will say what we know.

It is a good index. We want that established before anything else, because the usual way to dispose of a number like this is to find something wrong with the number.

Fourteen quarters. No revisions. No methodology disputes worth the name. It correlates, in the direction anyone would predict, with transit frequency, with the count of places a person can sit without buying something, with rent as a share of income, with hours worked, with the distance from a dwelling to the nearest person the occupant could telephone at eleven at night without apologising first.

That last one does most of the work. We were surprised. We are not often surprised.

The index goes up.

It has gone up in every quarter but two, and in those two it was flat, and in one of those two there was a hurricane, which we mention because a hurricane appears to be one of the few things that reliably moves it in the other direction. People check on each other. Then it resumes.

We are told the index is cited. We believe this. It is cited in three state plans, a foundation strategy, and a document from a body we had not previously heard of. It is described in each as a priority.

Nothing follows.

We want to be exact about this, because it is our whole subject.

It is not that the number is disbelieved. It is not that anyone opposes it. It is that when we go looking for where the cost lands, we find it lands entirely on individuals, one at a time, at home, and that there is no ledger anywhere in this state with a line in it that the cost could be entered on.

A pothole has an owner. It appears in a department's budget, and the department is scored, and a person can telephone and complain and the complaint is logged and the log is a number and the number is reported. The whole machinery exists and it exists because somebody's tyre.

This has no such machinery. There is no department. There is no complaint mechanism, and if there were, the population most affected by the underlying condition is definitionally the population least likely to use it, which is a sentence we have now written and would like to move past.

So the index is measured well, published on time, cited accurately, and enters nothing.

We hold a position on this, and it is not a trade.

The Institute has a problem numbered ten. It is in two parts. The first part is the conjecture and the second part is whether anyone can get Banana to open up. We have read the statement. It is undated, as they all are, and it does not explain itself, as they never do.

We understand it now in a way we did not before.

The Institute can state the first part precisely. It has done so, and the statement is sound, and it will still be sound in a hundred years. The second part is a beanbag with two animals on it and no method at all, and the Institute has published nothing on it and we do not think it can.

The index is the first part. It is exact. It will be exact next quarter and the quarter after.

We do not know anyone who is working on the second part. We would like to be corrected on this and we have left the address at the foot as usual.

Mandy writes on markets for Turtle Space. The column appears monthly and is expected to contract.