I would make sure you have full financials, which I'm assuming if you have a good CFO he has already advised you to. This includes footnotes addressing each line item. Anyone can post numbers in excel as others have pointed out. Your footnotes show you understand your business. But some of this depends where you are with your startup too I suppose.
I do know people who gained investments with simple pro-formas that were basically one sheets. I never would, but it would be inaccurate to say it never happens. If you are detailing it out you will likely have 100-300 rows in excel just to cover the below.
I would do monthly for 3 years with a year to year summary:
Cost of Sales
Gross Profit Margin
Salaries, wages, SS, Medicare, Futa, Suta, Insurance, Payroll, rent, utilities, D&O insurance, Depreciation Expense, accounting, legal, telephones, postage & mailing, Internet, travel, meals, supplies...etc as it applies.
STATEMENT OF CASH FLOWS