Help Needed With Nested Formula

Hi all,

I hope someone can help me, please.
I am busy working on a spreadsheet and trying to streamline it a bit.
I am trying to reduce the number of columns on the sheet, as it's a rather big spreadsheet, and involves a lot of scrolling from left to right.
I would like to find out if someone can help me with a formula for the following: (I want to include a summary at the bottom of the spreadsheet)

Cell C24 must contain the TOTAL number of km's travelled for "staff" - the formula must check if column C contains "staff" and then deduct the value in column D from column E

I was using a column with a formula to sum whatever info I wanted, but I want to reduce the number of columns in this sheet. I have attached a small sample of the sheet.
I would appreciate any advice or assistance.
Many thanks,
Angelique

Administrative Note:

We would very much like to help you with your query, however the thread title does not really convey what your request is about. Tell us what you are trying to do, not how you think it should be done.

Please take a moment to amend your thread title. Make sure that the title properly explains your request. Your title should be explicit and not be generic (this includes function names used without an indication of what you are trying to achieve).

Please see Forum Rule #1 about proper thread titles and adjust accordingly. To edit the thread title, open the original post to edit and then click on Go Advanced (bottom right) to access the area where you can edit your title.

(Note: this change is not optional. No help to be offered until this moderation request has been fulfilled.)

Your new title still doesn't tell us what you are trying to do.

Please change it to this: "Summary Travel Statistics: Add Mileage with Criteria".

Once this is done, you can receive help.

Thanks.

Administrative Note:

I really think you need to read the rules ...

We would very much like to help you with your query, however it has been brought to our attention that the same query has been posted on one or more other forums and you have not told us about this. You are required to do so.

Please see Forum Rule #3 about cross-posting and adjust accordingly. Read this to understand why we (and other sites like us) consider this to be important.

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