Originally Posted by
Adlerdriver
I have a partial solution for you. It is mind boggling that excel doesn't have this capability built in already.
Select the columns you'll be entering your OOOI times in and select "format cells".
In the box that opens, make sure the "number" tab is the one selected (it's the first one, so it should be).
Click on "custom" in the category section on the left and then enter this: 00\:00 in the blank space under "type" and click "okay".
That will allow you to enter 4 digit times without colon in the columns/cell you custom format that way.
You can do a simple subtraction formula to compute block time in a "Block Time" column by subtracting the cell value in your "in" column from your cell value in your "out" column. Assuming your out/off/on/in columns were A/B/C/D with the block time column in E, your formula in E2 would be =D2-A2. With your example of out at 0800 and in at 0922, I was able to get a displayed block time of 01:22.
Ehh, not exactly.
That technique allows you to type 800 and have it display as 08:00, but the value of the cell is 800.
When you subtract 800 from 922, you get 122, and it's displayed as 1:22 -- looks right, but ...
Use 1:55, 2:00, 3:05, and 3:20 as the times ... the values 155, 200, 305, and 320 display as desired, but when you subtract 155 from 320, you get 165, which displays as 1:65 ... oops.
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To the OP:
Why do you need it in tenths? I haven't converted minutes to tenths in over 15 years.
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