Table Design

[Hunter]

Hello all, new to the forum ... actually this is my first post!

I need help with designing a table that will store shipping rates. currently I have 4 origin plants with shipping rates from 2 carriers to 10 destinations. I have the table setup for each carrier and its working, but the rates change annually and I am trying to figure out how to handle this. I could change the rates in these tables every year but then the historical data will be inaccurate? I will greatly appreciate any help on this

The table is currently structured like this;
ID
Destination


Plant1Rate
Plant2Rate
Plant3Rate
Plant4Rate

Thanks for reading

[pbaldy]

For starters, the normalized design would be

ID
Destination
Plant
Rate

4 plants would be 4 records. To your question, your transaction table can have a field to store the rate used for that transaction. Then when you change rates in this table, historical data is not affected.