Change the format of the cell to personalised format to the following:
(might be other ways of course but this works… feel free to comment)

For numbers
_ * ###0_ ;_ * -###0_ ;_ * “NA”_ ;_ @_
(replace NA by any value or just nothing)

For percentages
_ * ###0%;_ * -###0% ;_ * “NA”_ ;_ @_
(replace NA by any value or just nothing)

Tweak according to needs…