userform checkboxes for calculations of annualizing income and expenses

hello,

I have created a userform where it can annualize income and expenses of multiple operating statements on my cashflow worksheet. Currently, I am able to annualize all the income and expenses for the whole operating statement. But what I want to do is be able to annualize just a specific expense (like taxes in particular) or income (like misc income in paritcular). I understand that one can write a bunch of case statements or if-then statements, but i was wondering if there is more efficient way to achieve this goal. is maybe running an array more efficient? please help


thakns