Pin Connector Strength Data - Determining Tensile

I hope someone can help me,

I want so simulate a pinned connector which fastens one component to another (Disc to Shaft).

The picture below illustrates my model (Figure 1). The hole diameter for the pin is currently 5 mm, Solidworks asks the user to input a tensile stress area, (Figure 2).

My understanding was that the Pin Tensile Stress Area (Figure 2 ) would refer to the area of the pin that is in contact with the body,

(Diameter = 5 mm, length = 31.6 mm ∴ Contact area = 496 mm)

Solidworks however requests a value of less than or equal to the the area of the pin diameter (19.635mm²) (Note Figure 3).

Could someone please explain to me what is happening here, am i missing something that is blatantly obvious?

Thanks

Ryan