This document discusses calculating chair cost and net income for an optometry practice. It defines chair cost as the costs associated with providing patient care. It provides an equation for calculating chair cost by subtracting operating expenses from fixed costs and dividing the result by the annual number of patient visits. The document also gives an example of how to determine net income per hour by subtracting the calculated chair cost per hour from the provider's revenue per hour. Finally, it emphasizes evaluating the three P's of patients, product, and profits for the practice.