those two images are clearer i do not get this

= Homework: A... Question 16, Additional ... An economy produces only two final goods: fish and berries. The table shows the quantities produced and the prices of these final goods in 2020 and 2021. The base year is 2020. By what percentage did real GDP change in 2021? In 2021, real GDP changed by percent >>> Answer to 1 decimal place. >>> If your answer is negative, include a minus sign. If your answer is positive, do not include a plus sign. In 2020 Item Fish Berries Quantity 130 40 Price $2 $6 Quantity In 2021 Item Fish Berries 90 65 Price $4 $8