determine if a customer has not paid in x months

[nelsok]

i have a spreadsheet with customers in column a and the associated monthly revenue from each customer in the next 25 columns.

I want to be determine if there are 0's in the x most recent months.
where x is any number.

so if i want to know if we recieved no revenue from a customer in the last 1 months it would be

assume b2:z2 are monthly dates 1/1/2007, 2/1/2007, etc...
=if(hlookup(match(now(),b2:z2,1),b2:z2,2,0)<=0,"not an active customer","active customer")

i just dont know how to do this for more than 1 month.

 

[tusharm]

Suppose you have the number of months of interest in E5. Then, use the formula
=COUNTIF(OFFSET(B2,1,MATCH(NOW(),B2:N2,1)-(E5),1,E5),0)=E5
where B2:N2 represents the first of each month and the payments are in row 3.

 

[nelsok]

thanks... if i am understanding the formula correctly, the formula returns true if the line does not have revenue within the number of months in e5.