Economists often look at retail sales data to gauge the state of the economy. The accompanying table shows a portion of seasonally adjusted monthly nominal retail sales for 2019, measured in $ millions. Also included in the table is the corresponding producer price index (PPI).
Month Sales PPI
January 444247 194.3
February 444305 195.4
March 438070 197.4
April 451447 199.2
May 453032 199.1
June 453150 197.0
July 457179 197.5
August 459267 196.4
September 458897 195.9
October 459486 196.6
November 461186 196.5
December 460672 196.4
a. How many times were nominal sales below that of the previous month? (Pick a number between 1 and 11.)


b-1. Use the PPI to compute sales in real terms. (Round your answers to the nearest whole number.)


b-2. How many times were real sales below that of the previous month? (Pick a number between 1 and 11.)


c. Compute the percentage increase in nominal as well as real retail sales in 2019 (January to December). (Round your answers to 2 decimal places.)