Need to get hours to feed in to another worksheet depending on the choice

[excelfan99]

So I'm at a company where I made a daily excel spreadsheet where they can pick from a dropdown list of projects and pick which one they worked on and write a number of hours for how long they worked. They want the number of hours they worked to then subtract from a monthly spreadsheet that displays the number of hours left before they're finished. The problem is that each project has a different number of hours required, and each person in the company gets their own daily spreadsheet. I need the numbers on the monthly spreadsheet to automatically subtract itself whenever the daily spreadsheets gain a new entry. For example, let's say the project is A-150. On the monthly sheet, the number of hours required for project A-150 is 400 hours. Bill submits an entry that says he worked 100 hours, and Bob submits an entry that says he worked 50. I would need the monthly spreadsheet to automatically notice that Bill and Bob submitted 100 hours and 50 hours of work, and then subtract it from the 400, leaving a total of 250. The problem arises because there are many other projects besides A-150 that Bill and Bob can submit hours for. I would need each project on the daily spreadsheet to subtract itself from the correct project on the monthly spreadsheet.

[ranman256]

Bad idea to use spreadsheets. This is a database project.

However, I would say for methodology....
Someone would have to manage the hours. The hours on the personal wb would have to be added to the Master monthly hrs wb.
If 2 people tried to do this at the same time , there'd be an error.

Id say, the user would email the wb to the 'handler', then they would click a macro to add the personal hrs to the master list and subtract Project hrs.