Rarity Index change 68 to 69 [opgelost]

When I documented this note on Numista a few months ago the rarity index was 68. Was updating my Excel sheet and just checked this note, the Rarity index is up to 69.
Did I make a mistake the 1st time or is such a thing possible. Does it imply a few people have deleted the notes and hence the rise from 68 to 69. Just wondering if the experienced panel had any thoughts.
100 pesos oro 2011-2013

It's possible. I just pulled up a cached page of this coin from 15 Apr 2021 and the NRI was 70. Note the differences in the frequencies.

15 Apr 2021


13 Jun 2021

Thanks rsirian1.
This is interesting. I always thought that with time the rarity index would keep falling.

I think in general that's true but with high NRI numbers they can be affected with just a few people adding or removing coins/banknotes. An NRI of 69 means about 42 members while an NRI of 68 is about 45 members.

Thanks