Excel Tips

See
https://www.reddit.com/r/AskReddit/comments/83wbqh/what_are_some_useful_excel_formulas_to_know/

IndexMatch
INDEX(MATCH()) is the best for indexing items. More versatile than H- or Vlookup.
Concat is fantastic to put data into strings for overview of your work.
=CONCAT("There are ";F3;" uncategorised expenses") for instance.

..

A SUM() won't work if you apply a filter. You need to use SUBTOTAL() instead
E.g. =SUBTOTAL(9, A1:A50)
sums values visible in the filter in column A between rows 1 and 50.
(There are a bunch of Subtotal functions. #9 is Sum)

see also
https://excelmacromastery.com