Swifty Corporation began operations on December 1,2019 . The only inventory transaction in 2019 was the purchase of inventory on December 10, 2019, at a cost of $21 per unit. None of this inventory was sold in 2019. Relevant information is as follows. During the year 2020, the following purchases and sales were made. The company uses the periodic inventory method. Calculate price index. (Round answer to 4 decimal places, es. 2.7653.) Price Index