Question: Exercises 15.16 refer to Tran’s Furniture Store, which has maintained monthly sales records for the past 48 months, with the following results.

Do you see any evidence of autocorrelation in this data?

Month Sales Month Sales

1 (Jan.) $23,500 25 (Jan.) 31,000

2 21,700 26 30,400

3 18,750 27 29,800

4 22,000 28 32,500

5 23,000 29 34,500

6 26,200 30 33,800

7 27,300 31 34,200

8 29,300 32 36,700

9 31,200 33 39,700

10 34,200 34 42,400

11 39,500 35 43,600

12 43,400 36 47,400

13 (Jan.) 23,500 37 (Jan.) 32,400

14 23,400 38 35,600

15 21,400 39 31,200

16 24,200 40 34,600

17 26,900 41 36,800

18 29,700 42 35,700

19 31,100 43 37,500

20 32,400 44 40,000

21 34,500 45 43,200

22 35,700 46 46,700

23 42,000 47 50,100

24 42,600 48 52,100