A good indicator of how well the office is collecting its accounts is the percentage of receivables that is more than 90 days old. If the percentage is unusually high, something is wrong in the office. Again, a high percentage could be traced to a systems problem, a people problem, or a combination of both. A good benchmark for most medical practices is to keep receivables more than 90 days old at less than 15 to 20 percent of the total amount of accounts receivable. A good specific benchmark would be that no more than 18 percent of the accounts receivable should ever be 90 days or older. Medical practice statistical surveys, such as the one produced by the Medical Group Management Association, could be used for comparison.