Calculating daily and weekly hours worked; updating most recent excel row based on date

Hi all,

I'm trying to track my hours worked in graduate school on various activities (e.g., writing manuscripts, programming experiments, etc.). I've setup my excel file to have a shorthand for date, so that each row marks the beginning of a new day (e.g., J1 = June 1st). On each row are empty cells that represent the total number of hours worked that day (e.g., 1.25 = 1 hour 15 mins). At the top, each column is marked by activity (e.g., writing, programming, etc.). On the side, I have a grid setup that enables me to type my start and stop time, with a separate start/stop time for each activity.

I want to enter my START and STOP times throughout the day after working on various tasks. I then want that information to be automatically added to the appropriate cell in the row that represents the current date. For example, it might look something like this:

ACTIVITY: Writing
START: 10:00 am
STOP: 11:00 am
TOTAL: 1.00

That information would then need to be added to the right cell based on: 1) the present date, 2) which activity this represents. Thus, it would find the correct row based upon date, and then the column information would never change (i.e., writing would always be in column X, programming in column Y, etc.).

The point of doing this is so that I can quickly enter my START and STOP information throughout the day, and my overall total for each day will be recorded quickly (so that if I take breaks, I can come back and re-update my START and STOP times to keep adding to my daily values). In this manner, I can get a sense of how much I typically work on any given task. Additionally, I have created a grid that I would like to use to keep running daily and weekly averages of my overall amount of hours worked broken down by activity.

If need be, I can try to clarify what I need if it is at all unclear. I specifically do not know how to write the appropriate code to dictate which row the information should be placed in, nor do I know how to subtract times and obtain a "text" value for hours (such as 1.25).

I have attached the Excel sheet I have created to give everyone an idea of what I'm trying to accomplish.

Thanks,

PoLyGLoT