The Resource Utilization selection criteria is used to specify additional settings that will influence the layout of the resulting grid.  You can choose:

Color by Booked Percentage:

Using this control, the resulting grid will display each cell colored according to the user defined ranges for the available colors (green, yellow and red), base on the users booked percentage during that period.  The users booked percentage is calculated as:

Planned Hours/(# of business days in range * business hours in work day) across all projects for this period.  As such a user may have an empty cell that is reporting to be over booked (due to existing plans for other projects / tasks).  Actual hours entered on timesheets are not considered in this calculation.

To understand what a user is specifically planned for in a period (on this and other projects), you can view the same user in a Resource Allocation report (perhaps in another browser tab).

Note that the resulting grid may include two shades of each color.  The muted colored cells represent the uneditable (i.e. grayed out) version of a particular utilization level.

Given the following example, items would be included as follows:

From 0 to 50 - Yellow -- items < 51

From 51 to 100 - Green -- items > 50 and < 101

From 101 to 999 - Red  -- item > 100

Limit Resources by Booked Percentage:

Using this control, the resulting entries displayed on the grid will be further filtered base on a user's booked percentage being Less than and/or More than stated % Booked amounts.  For the purposes of this control, the user's total booked percentage across all displayed cells is considered (not individual grid cell values), that is, the value in the "Total" column will be compared to that user's expected total business hours to determine their inclusion in the grid.