When using Excel logic functions such as
SUMIF which involve ranges being evaluated based on criteria, you cannot select the criteria from the range of data you are evaluating. This is a very common error.
The example below is an extract of some data with the
COUNTIF function being used to analyse the number of respondents living in each area:
Notice how carefully the cells have been laid out for the calculation of the answers, specifically the labels in range E15:E20. This allows you to use the labels in your functions & formulae and facilitates the easy and correct copying of your functions & formulae. The labels and headings also make it really easy for someone to understand the data you are presenting.