button to update a field only when another field value = X

I'm trying to update all costs in our system that where the carrier is "APL" with this button

The current Table has 2 fields:

1) url formula field - button to action the amount
2) Numeric Field - the amount that will be entered into Field #77

user enters in the amount and then clicks the button and all costs where the carrier is "APL" now has the value that the user entered into in #2 above.

Hope this clarifies a bit.