Explanation:
When you want to use the greater, less or equal signs ("<",">","=") in the criteria range of the COUNTIF formula you should include the expression within quotation marks.
Example: =COUNTIF(A1:A8,">=4")
Problem:
A problem arises if you want to use a cell reference in place of the number.
It is wrong to include it within quotation marks.
=COUNTIF(A1:A8, ">=B1") since Excel will identify the cell reference as a string
Solution:
The key is to include only the signs (<,>, =) within quotation marks and use the “&” operator to join (CONCATENATE) them with the cell reference:
=COUNTIF(A1:A8, ">="&B1)
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