populating field with USPS postage rates

[gringotani]

I need to populate a table field called “freight-amount” with the USPS “Priority-Mail class” rates, which are based on the package's weight and zip code... All the packages would always originate from the same sender (zone#1). I am wondering if there is a simple predeveloped method to automatically obtain this data or if I need to make my own queries to calculate the value, based on the USPS rate table , weight and zone (zip code prefix).
Please advise on the most practical method to accomplish my objective and what data-source would provide me the required info. I am very savvy with MS Access macros/queries, but I do not know VBA .
Thanks very much in advance, Nathaniel

[rpeare]

You'd have to have a table that had a list of zip codes and what USPS zone they were in.

Use this chart:

http://postcalc.usps.gov/zonecharts/

you can put in your zip code and get a list of the appropriate zones then when you're running your process you can just look it up based on the first 3 digits of the target zip code.

Then you'd have to have some method to cross reference weight with zone (I don't know if it's a simple operation i.e. weight * (zone * some factor))

You wouldn't need any vba to do this, just another table that stored your zones by postal code (the link I gave you) and another table that listed zone and whatever the factor would be