A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Here's the best way. Insert a new sheet, and copy the Name OCA ID columns from 2014 into columns A:C. Then, in D2 (assuming you have headers in row 1) enter the formula
=A2 & " " & B2 & " " & C2
and in cell E2, enter 2014. Then copy those cells down. Copy the information from 2015, and put the cells below the list from 2014, and do the same for column D and E (except use 2015 in E). Repeat for 2016.
Then select columns D and E, and insert a pivot table. Use column D as the row field, column E as the column field, and column D as the data field. You will get a table that shows which years each combination appeared.