Rarity Index

Sometimes when a banknote is not on a swap offer, it has the rarity index in 90s. Why is it not 100 when there's no one swapping it? Or does it mean that a very few members may have it (and don't want to swap it) which is why it's under 100?

https://en.numista.com/help/what-is-numista-rarity-index-nri-79.html

I wonder which notes and coins have 01 NRI.

No coins or banknotes have an NRI of 1. I believe this is the banknote with the lowest NRI (5):

N#201805

There are numerous coins with an NRI of 2.

But this just doesn't make sense! I mean there must be billions of one dollar bills out there which should make it 1. Don't think there would be a country in the world without the availability of USD.

By the way, which coins have 2?

It makes sense considering many (most?) Numista members don't collect banknotes.  I currently have 12 $1 bills in my pocket but zero in my collection.

Is there any coin which is rated 1 on the Numista Rarity Index?

But shouldn't they also take into the account how easily a note would be available if someone wanted to get one? I think this is an important factor.

It is, within the Numista community, by how many members have it on their swap list.  It can't take into account how easy it is to buy one on ebay.

N#353547

It's a recent note with seven people are offering it and yet its its NRI is 70, this index really is a mystery. 🥴

thegamesbond

N#353547

It's a recent note with seven people are offering it and yet its its NRI is 70, this index really is a mystery. 🥴

Not really. It's a 2023 note from Poland.  Hasn't had enough time to really get too far from Poland in sales/trades. Note that 5 of the 7 live in Poland.

To a coin/note have a NRI 1, every single Numista member must have one in their collections. Not impossible but certainly not happening.

Geison

To a coin/note have a NRI 1, every single Numista member must have one in their collections.

I don't believe that's necessarily true since the NRI is also affected by the number of coins available for swap.