In the Census Bureau’s Excel Statistical Testing Tool, the sample margins are preceded by “+/-.” Does the tool still calculate statistical significance correctly without the “+/-“ signs? I have to manually enter many of these margins (rather than simply copying from data downloads), and Excel will simply not allow me to enter those characters before numbers. It keeps forcing me to correct them.

www.census.gov/.../statistical-testing-tool.html

I don’t see documentation from the Census Bureau instructions that specifically address this. The “worked example” spreadsheet in the Testing Tool file includes an example with parentheses around the margins, which Excel will allow, but I’d prefer to keep the editing to a minimum – i.e., it would be easier if the +/- is not really necessary to calculate significance.

I’ve also tried copying and removing the +/- symbols and the statistical significance results appear to come out the same for a few examples, but I’d prefer to have some authoritative confirmation of this. Thanks!