为什么不是斜率呀

问题如下：

Based on the regression, if the CPIENG decreases by 1.0 percent, the expected return on Stellar common stock during the next period is closest to:

选项：

0.0073 (0.73 percent).

0.0138 (1.38 percent).

0.0203 (2.03 percent).

解释：

C is correct. From the regression equation, Expected return = 0.0138 + (−0.6486× −0.01) = 0.0138 + 0.006486 = 0.0203, or 2.03 percent.