I do a lot of timetables where we use letters of the alphabet to represent
different shifts for example E = 8.25 hrs work, E1 = 8 hours. I usually do
all the timetables in excel. I was wondering how do I assign numerical values
to each letter/code so that it adds up the total time in one cell? I want the
letters to remain but for them to have numerical values and then have one
cell that adds up all the hours worked as a number.

For example if one person works E, E, E, E on four different days (i.e. 8.25
hours on four different days/cells) how do I get excel to give E an value of
8.25 so that the box that adds up the total values shows the total (33)?

Is there a function where I can give values to specific letters in a block
rather than putting in a formula in each cell (if there is one of course) ?

This sounds rather complicated but would save me a lot of work. I would be
sooooo grateful to anyone who could help me.