Calculate percentage using functions

Question

I have an Excel workbook (Office 2010) that lists multiple different spreadsheets (offices) in our organization. We use this workbook to keep track of their "errors" in turned-in documents (example only). I'm trying to figure out a good way to determine, through automation (functions) the percentage of documents that have had errors in them. I want to determine the percentage of documents looked at versus the amount of errors, completely ignoring the amount of errors. So if I looked at 10 documents and 7 of those had at least one error, the office's percentage of errors would be 70%.

Is there any easy way to do this?

I've tried a few functions but I continue to get errors. I show a sample sheet (one office) below. This example is similar across multiple sheets and there is a dashboard that I would like to display all of these statistics based on offices.

workpaper        DISCREPENCIES          
Paper   Spelling Grammar Punctuation Total Errors/Paper 
A.36.7     1       0       1               2
A.36.8     0       1       1               2
A.36.9     0       1       0               1
A.36.10    0       0       0               0
A.36.11    1       0       0               1
A.36.12    1       1       1               3
A.36.13    2       3       0               5
A.36.14    0       0       0               0
A.36.15    0       0       0               0
A.36.16    1       1       1               3
                           Total Errors    17
                           Total Documents 10
                 Total Documents w/ errors 7
                      Percentage of Errors 70%

I can do all of this manually but I would like to find a way to do this across all sheets since there are a quite a few and output them to a "dashboard" that has all offices listed in rows.

Answer 1

One way is to look at the number of worksheets with 0 errors in them. Then subtract that percentage from 100%. For example in G5:

=COUNTIF(E3:E12,0)/COUNT(E3:E12)

and in G6:

=100%-G5