Projections based on a predefined percentage of total

[djasper6]

I am trying to forecast numbers based on actuals and a predefined total. For example the total is 400,000. The actual inputs that i have are 2000 , 3000 and 6000.
The original projected percentages are 4% 5% 6% of the total. The actuals come in at .5%, 1.25% and 2.75%. The percentages of the total are cumulative.

The schedule has a predefined percentage that the funds should be drawn at. If we deviate from the draw i want to auto calculate based on the actuals the necessary fund draws to get back on course with the information. Looking at the sheet, I've included the projected draws and left the space open for actuals so when i include them i can compare the numbers and the percentage of the total and make the adjustment.

I am looking for something that makes the adjustment based on the information in the actual column and adjusts on its on depending on the number of actuals that are in given.