Using a spreadsheet book I am using multiple tabs. In one tab I have a drop
down list of "Customers", "Sales Price", "Quantity" and "Products." I have
another tab that has "if" & "and" functions that test to see what
"Customers", "Sales Price", "Quantity" and "Products" are being referred to.

What I want to do is have Excel record the data when I am referring to a
specific customer/product/price/quantity, but when I pick a new customer from
the drop down list I want the data for previous customer to remain. As of now
when I choose one customer the other customers data turns to "False" given
the if & and functions. How can I have the data change only when I refer to
it via the drop down list and not change when I am not referring to it in the
drop down list.