Posted this question yesterday but I'll be darned if I can't locate the thing in any forum!

Ok, I have a workbook with two worksheets.

Worksheet 1
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Column A = 5-digit Zip Code
Column B = Zip+4 low end (4 digits only)
Column C = Zip+4 high end (4 digits only)
Column D = Sales Tax Jurisdiction Code

Worksheet 2
---------------
Column A = Customer ID number
Column B = 5 Digit Zip Code
Column C = Zip+4 (4 digits only)
Column D = Formula for Sales Tax Jurisdiction Code

I need to be in Worksheet 2 and look up the 5 digit zip code from W2/C:B and match to W1/C:A. Once it finds the correct 5-digit zip, I need it to loop thru the zip +4's on worksheet 1 (within the correct 5 digit zip) until it finds the 4 digit zip that falls =< W1/C:B AND >= W1/C:C. Once the correct 5-digit zip is found and the proper row for the 4 digit zip I need it to return the Sales tax jurisdiction code from W1/C:D to W2/C:D

Can anyone help me get started?