Data Type Duration (duration field: A type of field whose content is expressed as a duration of time. Examples include the Work, Duration, and Delay fields. A duration field includes the duration unit, such as hour, day, or week.)
Entry Type Calculated (calculated field: A field in which the value is determined by Project based on information in other fields. Project may recalculate the value automatically or when you specify, depending on your choice of calculation settings.)
Description The Work Availability field contains the maximum amount of time a work resource (work resource: People and equipment resources that perform work to accomplish a task. Work resources consume time [hours or days] to accomplish tasks.) is available to be scheduled for work (work: For tasks, the total labor required to complete a task. For assignments, the amount of work to which a resource is assigned. For resources, the total amount of work to which a resource is assigned for all tasks. Work is different from task duration.) during any selected time period, as distributed over time. The displayed amount of work, or person-hours, is based on the resource calendar (resource calendar: A calendar that specifies working and nonworking time for an individual resource. A resource calendar differs from a base calendar, which specifies working and nonworking time for more than one resource.) and the Resource Availability table in the Resource Information dialog box. This field also shows a timephased (timephased: Task, resource, or assignment information that is distributed over time. You can review timephased information in any available time period in the fields on the right side of the Task Usage and Resource Usage views.) representation of any changes in unit availability (unit availability: Amount of time, expressed as a percentage or a decimal number, that a resource can be scheduled for assigned work. It refers to the availability of a resource; for example, a resource may be available 50%, 100%, or 300% of full time.) for different time periods.
How Calculated Microsoft Office Project calculates work availability (availability: Indicates when and how much of a resource's time can be scheduled for assigned work. Availability is determined by project and resource calendars, resource start and finish dates, or the level at which the resource is available for work.) distributed over time based on the resource calendar (resource calendar: A calendar that specifies working and nonworking time for an individual resource. A resource calendar differs from a base calendar, which specifies working and nonworking time for more than one resource.) and the Resource Availability table in the Resource Information dialog box. Project calculates work availability as follows:
Work Availability = Unit Availability * Time
Best Uses Add the Work Availability field to the timephased portion of the Resource Usage view when you want to display the maximum amount of work a resource has available for accomplishing any tasks (task: An activity that has a beginning and an end. Project plans are made up of tasks.) during the selected time period. Also use this field to show changes in work availability for different time periods, as established in the Resource Availability table of the Resource Information dialog box.
Example You have planned for four painters to work on your project in March and April, six painters in May through August, and two painters in September and October. In the Resource Availability table of the Resource Information dialog box, you have reflected these dates with units of 400%, 600%, and 200%. You add the Work Availability field to the Resource Usage view so you can see the changes in the painters' work availability through the months. You can also see their availability by day or by week.