Legal advertising—does it pay? To gain a competitive edge, lawyers aggressively advertise their services. Does legal advertising really pay? To partially answer this question, consider the case of an actual law firm that specializes in personal injury (PI) cases. The firm spends thousands of dollars each month on advertising. The accompanying table shows the firm’s new personal injury LO9 

Month New PI Cases 6 Months Cumulative Adv. Exp.
7 11 $ 41,632.74 8 7 $ 38,227.39 9 13 $ 39,779.77 10 7 $ 37,490.22 11 9 $ 52,225.71 12 8 $ 56,249.15 13 18 $ 59,938.03 14 9 $ 65,250.59 15 25 $ 66,071.85 16 26 $ 81,765.94 17 27 $ 66,895.46 18 12 $ 71,426.16 19 14 $ 75,346.40 20 5 $ 81,589.97 21 22 $ 78,828.68 22 15 $ 78,415.73 23 12 $ 90,802.77 24 18 $ 95,689.44 25 20 $ 83,099.55 26 38 $ 82,703.75 27 13 $ 90,484.38 28 18 $102,084.54 29 21 $ 84,976.99 30 7 $ 95,314.29 31 16 $115,858.28 32 12 $108,557.00 33 15 $127,693.57 34 18 $122,761.67 35 30 $123,545.67 36 12 $119,388.26 37 30 $134,675.68 38 20 $133,812.93 39 19 $142,417.13 40 29 $149,956.61 41 58 $165,204.46 Month New PI Cases 6 Months Cumulative Adv. Exp.
42 42 $156,725.72 43 24 $146,397.56 44 47 $197,792.64 45 24 $198,460.28 46 14 $206,662.87 47 31 $253,011.27 48 26 $249,496.28 cases each month over a 42-month period. Also shown is the total expenditure on advertising each month, and over the previous 6 months. Do these data provide support for the hypothesis that increased advertising expenditures are associated with more personal injury cases?
Conduct a complete simple linear regression analysis of the data, letting y = new PI cases and x = 6@month cumulative advertising expenditure. Summarize your findings in a professional report.