How is overhead margin calculated for material cost versus labor cost?

Material overhead is calculated using the unit cost.

EXAMPLE: Material

10 x 5.577 = $55.77. To calculate a 2% overhead, take 5.577/.98 = 5.69081632653. Take 5.69081632653 - 5.577 = .11381632653. Round that number to .11 x 10 units = for an overhead of $1.10

EXAMPLE: Labor
Take the total cost of the labor amount such as 55.77/.98 = 56.9081632653 - 55.77 = $1.13.

Material overhead and calculated using unit cost, labor is calculated using total earnings amount.