Days in Between Orders Datedif?

[john62290]

Hi. I am looking for a formula that calculates the number of days in between orders for multiple accounts. If the order number is 1, it would be blank but would like a formula to return 9 for 4/10/2024 ABC and 5 for 4/15/2024 ABC. Thanks!

Date	Account Name	Order Number	Days in Between Orders
4/1/2024	ABC	1	-
4/2/2024	XYC	1	-
4/2/2024	AAA	1
4/10/2024	ABC	2
4/11/2024	LLL	1
4/15/2024	ABC	3
4/17/2024	ABC	4
4/20/2024	XYC	2
4/30/2024	XYC	3
5/1/2024	LLL	2

 

[MountainFog]

=LET(co,$A2,lo,INDEX($A$2:$A$11,XMATCH(1,($B$2:$B$11=$B2)*($C$2:$C$11=($C2-1)))),IF($C2=1,"",co-lo))

 

[john62290]

=LET(co,$A2,lo,INDEX($A$2:$A$11,XMATCH(1,($B$2:$B$11=$B2)*($C$2:$C$11=($C2-1)))),IF($C2=1,"",co-lo))

Thanks! Are you able to explain how that works. What do co and lo mean?

 

[MountainFog]

LET function allows you to assign variable names to be used later in the function. I chose CO for Current Order, and LO for Last Order, but you can use anything you want. Alternatively, you could make the same function without using let, but it would be longer and harder to understand.