Consolidating Data from Multiple Users into a Single Workbook
So far, we've discussed sharing workbooks and tracking revisions on a shared workbook file users open from a central location on a company network. But revision tracking can be useful in another set of circumstances as well. You can create a workbook, turn on revision tracking, and then make copies and distribute them to a group of people. If you want a group of department heads to work on draft budgets, for example, give each one an identical workbook with revision tracking turned on. When they return the copies with their changes, you can merge the copies into a single workbook, and then review and accept or reject individual changes.
Tip from 
If there is any chance that the process of distributing, collecting, and merging workbooks will take longer than 30 days, be sure to change the time period you specify to maintain the merge history. Select Tools, Share Workbook, click the Advanced tab, and enter a number of days in the Keep Change History For box. To be extra safe, set this value to its maximum of 32767.
When creating the worksheet for distribution, follow these steps to be certain the merge process will work properly:
Create the workbook model you want users to fill in, complete with formulas and headings. If you want to lock cells or hide formulas, do so now.
Select Tools, Protection, Protect and Share Workbook, and check the Sharing with Track Changes box. To force all users to track changes and prevent them from disabling revision tracking, enter a password in this dialog box and click OK.
Confirm the password you just entered and click OK. Excel displays the Save As dialog box.
Give the file a name and click Save. This is your master workbook.
Without making any changes to the workbook, click File, Save As, and make a new copy for each person to whom you plan to distribute the workbook. Make sure each copy is identical, and save each one under a different name.
After you receive the filled-in copies from each co-worker, follow this procedure to merge the workbooks:
Open the master workbook you created before distributing the copies.
Click OK to merge the workbooks.
Tip from 
There are many ways that merging workbooks can go wrong. If you get an error message when attempting to merge one or more workbooks, try copying the information from one workbook and pasting it into the master copy. Be certain you're not overwriting important data when you use this technique.