Department R had $4,700$ units in work in process that were $79\%$ completed as to labor and overhead at the beginning of the period; $37,600$ units of direct materials were added during the period; $39,700$ units were completed during the period; and $2,600$ units were $20\%$ completed as to labor and overhead at the end of the period. All materials are added at the beginning of the process. The first$-$in$,$ first$-$out method is used to cost inventories. 

What was the number of equivalent units of production for conversion costs for the period?

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