I want to know the % of people who have NOT returned to our office after consultation (success rate) For example 51 people had their 1st visit and out of those 51 people only 4 needed to make a second appointment. I want to work out how many people did not return (47) as a percentage using an excel formula. Everything I have tried so far has not worked, Any ideas?

Many Thanks in advance

Why not use this formula? =(C8/C7) where C8 is the cell with 47 in it and C7 is the cell with 51 in it. In "format cell", set the number tab to "percentage". Change the cell values as needed and the percentage will always be current.