The following sections provide a step-by-step guide for properly filling out Obligation Worksheet A.1 Worksheet A is for child support in sole and joint custody arrangements.2 It does not apply to “shared custody,” which is joint custody where each party has physical custody for approximately equal time.3 It must be used in a particular manner in “split” custody arrangements in which the parties have two or more children, and each parent has sole custody or is the domiciliary parent of at least one of those children.4 For simplicity of presentation, this manual proceeds as if the case requires use of Worksheet A. The principles of determining the amounts of income and expenses to be entered onto the worksheet generally apply even if Worksheet B is used.