Comparing information on two excisting lists.

[Rick]

Hi,

I'm looking for a solution to the following problem.

I have two lists each containing around 2,500 account
numbers.
[1] The first list contains the customer id of the
previous quarter.
[2] The second list contains the customer id of the
current quarter.

I want to accomplish the following:

[Task 1] Create a list of all the customer ids of the
previous quarter + current quarter.(Combing both lists
into one and then removing the duplicate customer ids.)
[Task 2] Create a list of all the customer ids that has
not done business with us this quarter. (If they were in
the first(previous)list and not in the second(current)
list.)

I will appreciate any help on completeing either tasks.
Thank You.

 

[ABCD]

(Task 1) * Add tags to both the lists so that just by
looking at the row you know which one pertains to the
current qtr and which one to the last qtr. This may mean
adding a column which just says 'CURR' or 'PREV'.
* Using the Data->Filter->Advanced Filter menu option, get
a list of unique account numbers.
(Task 2) Try a combination of IF, VLOOKUP and ISERROR with
the new list and the old one to determine what you want.