Just for completeness, it also exists this option limited to PUs only
<!-- Multiply PUs will multiply all PUs gained or lost during a turn. It will not yet multiply costs of units or any other costs, or starting PUs --> <property name="Multiply PUs" value="1" editable="false"> <number min="1" max="10"/> </property>
Theorically, you could rework this option as being "Multiply ...", where "..." would apply to whatever resource called exactly that way, in the property.
However, while this is a handy property, I don't think anyone will ever really want to use it to multiply anything else but PUs (its usage is about limited to the matter of defining placement limits relatively to the income, without having to set different production and unit placement for each single territory).
Basically, you use this property only in cases like you want all territories to give PUs equal to 2 or more times their placement abilities, and, this way, you can do it without having to set 2 values for each single territory. This is mostly for maps with maintainment costs, where you would have a lot more placement than remaining income for new units, or for having thigh placement limits without necessarily resorting to have the fodder costing only 2 PUs, that is somewhat impractical.
So, this is just a notice, but my actual suggestion is forget it and keeping this property working just as it is, as I don't think there should be really any reasons for using it for anything else but PUs.