An advertising firm wishes to demonstrate to its clients the effectiveness of the advertising campaigns it has conducted. The following bivariate data on twelve recent campaigns, including the cost of each campaign (denoted by x, in millions of dollars) and the resulting percentage increase in sales (denoted by y) following the campaign, were presented by the firm. A scatter plot of the data is shown in Figure 1. Also given is the product of the campaign cost and the percentage increase in sales for each of the twelve campaigns.

Campaign cost, x (in millions of dollars)	Increase in sales, y (percent)	xy
1.34	6.29	8.4286
2.96	6.53	19.3288
1.67	6.23	10.4041
3.85	6.79	26.1415
1.68	6.61	11.1048
2.24	6.64	14.8736
3.10	6.98	21.638
2.13	6.56	13.9728
3.13	6.49	20.3137
3.58	6.79	24.3082
4.00	7.06	28.24
1.99	6.80	13.532

What is the slope of the least-squares regression line for these data? Carry your intermediate computations to at least four decimal places and round your answer to at least two decimal places.

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