Assuming you have a bunch of tab delimited files w/out headers and the second column as a number, you could use the following powershell command to sum the values and output the result.

PS > $sum=0; ls | cat | %{ $.split(“`t”)[1] } | %{ $sum+=[int]$ }; $sum

Sample File:

a-count    7
b-count 233
c-count 32
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