Year Cash Flow

$0$$$625,000,000$

$170,000,000$

$2129,000,000$

$3183,000,000$

$4235,000,000$

$5210,000,000$

$6164,000,000$

$7108,000,000$

$886,000,000$

$990,000,000$

Most spreadsheets do not have a built$-$in formula to calculate the payback period. Write a VBA script that calculates the payback period for a project.