I have employees who have a guaranteed set number of hours each pay period. These employees are servicing customers and most of their hours are billable to customers. However, if they do not have enough work on their service hours to meet their guaranteed hours for the pay period, we add in the difference on a specific pay type to get them up to the minimum. In the event that they work more than the minimum, I would like to make an entry for negative hours against the pay type where we previously recorded the guaranteed hours shortfall. This is for the purpose of tracking time and allocating cost. These are all highly paid employees who are exempt. We track hours and related pay for cost allocation to projects.