A Ballpark Figure is a rough numerical estimate or approximation of the value of something that is otherwise unknown. Ballpark figures are commonly used by accountants, salespersons, and other professionals to estimate current or future results. A stockbroker could use a ballpark figure to estimate how much money a client might have at some point in the future, given a certain rate of growth. A salesperson could use a ballpark figure to estimate how long a product customer was thinking about buying might be viable.The reason why these professionals often rely on ballpark figures is because they provide an easily understandable way for people to get an idea about complex situations without needing all of the details. Furthermore, when it comes time to make decisions based on this information, more accurate numbers can always be calculated later on if necessary. In many cases, using ballpark figures can save time and help avoid misunderstandings since everyone involved has at least some understanding of what's being discussed even if it's not perfect.