I thought that keeping an attribute as a key figure meant it could have different values across time. If it was a regular attribute, it would only have one value.
However, as per the Model Config doc:
"When the value of an attribute of a master data type remains the same over time (for example, the attribute Product Price of master data type Product), you can define the attribute as a key figure. When such an attribute is loaded as a key figure, it should have the same value for all time periods"
So, having an attribute as a key figure: should it have the same value across time or can it take different values since there is a period attribute when it is a KF?