What is the difference between an outlier and a serious outlier in Statistics?

One type of investment's Lower Inner Fence (LIF) is 1.6875 and its Upper Inner Fence (UIF) is 5.3875.





Also, its Lower Outer Fence is 0.3 and Upper Outer Fence is 6.775.





Is the yield of 1.55 and outlier? or a serious outlier? please explain the answer if you know!! Thanks a lot.

What is the difference between an outlier and a serious outlier in Statistics?
I've never heard the term 'serious outlier'.





1.55 is outside the lowerinner fence but inside the lower outer fence





So based on what you describe id say an 'outlier' and only if its outside the outer fence would it be a 'serious outlier'





But I'm guessing I've never heard those terms.