Extract the irregular component by taking the normalized average of the ratio-to-moving-averages.
Make a table that shows the normalized seasonal indexes. Interpret what the index for January means relative to the index for July.
Store, which has maintained monthly sales records for the past 48 months, with the following results:

1457(6) 4( 855 S( 2 7 7 4 6 4 35 4 4 3 3 2 3 3 3 3 3 3 3 3 1-901 678 7 6 933 1469 () 1 2 3 4 5 6 7 8 Month Sales (S) 32.400 35,600 31,200 34.600 36.800 35,700 Month Sales (S) 37.500 40,000 43.200 46.700 50.100 52,100 37 (Jan) 38 39 43 46 48