Cheat Engine

[lawkduski]

Hello, first the explanation:
The game is Company of Heroes 2, Skirmish against AI (Custom game), you have 3 resources, manpower, Munitions and Fuel. now all 3 of those resources have an "Income rate" , for example my munitions are 500 (+45) that "+45" is the income per minute, it changes whenever you gain or lose a capture point or whenever you build munition caches etc, that is the value i want to change and freeze, say change to +75 and freeze it there. now i found the value by unknown initial scan and with decreased and increased values, and at the end i found the one single address that controls it, because my munitions income were +93 when i found the address, whenever i freeze it the income rate becomes +93 so i suppose this is the real value, which a "Double" Type value.
what i need help with: how do i find this address next time i want to change it? how do i edit this address say to +100 or more or less? how do i really edit this address? because the value is (4.38690277200995E-7) and i dont know what is that supposed to mean.
Note: the address is (911C99F4), is this fixed for future scans? is this ALWAYS the address that points to munition income? even for other fractions in game?
thanks.