# Identifying a massive change (increase) in the list items

Hi guys,

Is there any way to spot an abrupt (massive) change in the values of a list? For instance, I have a list of items (areas) 2, 4, 6, 8, 1000, 1100, 1500. As you can see the increase from 8 to 1000 is massive. Is there any node that can help extract the value at which this change takes place?

Thanks a lot!

You can compute the Relative Difference

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Thanks Martin, it seems that in this solution one has to visually identify the difference. I would like to make it parametric. For instance, we know that index 4 has the (1st) largest relative difference so the node identifies it and gives me the output value (i.e. 1000). I am trying different combination of nodes to see if it works and if you could share some further insight, itâ€™d be very helpful

Relative Difference + Sort

If you can test it against one fixed value (in the image : 63), then something like this?

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Sort works for the largest relative difference but not for the first largest relative difference as between 5000 and 1001 but I want the difference between 1000 and 8 so I can get the first largest relative difference. I know it is not really relative if we do not compare it with another value (because the first largest (abrupt increase) number idea is really vague) and I have to identify some sort of value so that the relativity is established. I am thinking about that.

Hi Antonie, yes. The second number 63, how did you decide that? Was it trial and run?
Thanksss!

Trial and run
If you are sure that there is a hard value you can find that will always works, Iâ€™d do thatâ€¦

If youâ€™re not sure about that, I think youâ€™d have to compare values to the mean and the standard deviation.
And it might not detect everything without some manual tweaks

If you use the image I posted above, and if you can have also drop values, it will create negative spikes, so make sure to add an â€śabsolute valueâ€ť component after the relative difference !

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Thanks a lot