Count-back "x" number of cells from when value goes negative

I am running a basic demand planning worksheet, which decrements inventory and uses conditional formatting to identify when inventory will run out. Now, I am looking for a way to identify the "Order Date" to place new PO's based on the number of days in the "Leadtime"(C2:C5) field. Any ideas?

Thanks

Try

=INDEX($D$1:$CE$1,MATCH(0,$D2:$CE2,-1))-$C2

You may need to add +1 to the end depending on which date you want to begin the counting from (Date it turned negative, or last date it was still positive)
This begins the count on the last day it was positive.

Nevermind, it was just formatting....Got it.

Thanks for the help!

Thanks for the lp. Next question will probably make me seem even more incompetent...

When I try using these in conditional formatting it just highlights all values, which clearly isn't working. WHen I enter the formula into a cell on it's own it returns a value of 42330(johnmo1) and 42331(bebo).

Am I just using the formulas you provided incorrectly? I apologize for my ignorance here. Thanks in advance for any further help

You're welcome.