How to determine non-standard deviation in a trend?

Question

Analytics

There is an array of data, for example, how to determine that 50 (the last element of the array) is a non-standard deviation for a given trend? or array 120 (the last element of the array) - non-standard deviation for this trend? [100, 99, 94, 92, 87, 50]

[100, 99, 94, 92, 87, 120]

Answer 1

Use a linear fit.