Returning a Value from a .bat File to CFEXECUTE

Question

I have a batch file with the following code to pull the current server CPU usage:

@echo off

for /f "tokens=2 delims==" %%i in ('wmic cpu get loadpercentage /value ^|find "="') do set /a cpu=%%i
echo %cpu%

Using ColdFusion's CFEXECUTE, I would like to run this batch file and return the echoed value:

<cfexecute name="#PathToBatchFile#" variable="Usage">
<cfdump var="#Usage#">

Running the above results in ColdFusion 2021 saying "Usage" is undefined.

The batch file can output the value to a file using the "outputfile" attribute --

<cfexecute name="#PathToBatchFile#" outputfile="#OutputFile#">

-- then I can use CFFILE to read it, but that seems rather roundabout. Anyone know what I could be doing wrong? Thanks!