The Finishing Department had $6,200$ incomplete units in its beginning Work$-$in$-$Process Inventory which were $100\%$ complete as to materials and $40\%$ complete as to conversion costs. $17,400$ units were received from the previous department. The ending Work$-$in$-$Process Inventory consisted of $3,200$ units which were $50\%$ complete as to materials and $40\%$ complete as to conversion costs. The Finishing Department uses first$-$in$,$ first$-$out $($FIFO$)$ process costing.

What are the equivalent units of production for materials during the period?