Difficult# Interpreting a Confidence Level for Slope: Dow Jones

APSTAT-1EV84F

In February of 2009, the Dow Jones Industrial Average (DJI) reached a low that it hadn't seen in 10 years. Since then, the Dow Jones has been steadily increasing. Analysts have been studying the relationship between the highs of the Dow Jones for each year since 2009. A computer regression analysis of the data is given below:

Dependent variable is: Dow Jones Industrial Average (DJI)

$R^2 = 93.33\%$

$s= 1116.14$ with $6-2= 4$ D.O.F.

Variable | Coefficient | s.e Coeff | t-ratio | prob |
---|---|---|---|---|

Constant | 8224.89 | 735.23 | 16.06 | 0.00001 |

Year | 1993.35 | 123.34 | 7.47 | 0.0017 |

Assuming all of the conditions have been satisfied, which of the following is a correct interpretation of "$90\%$ confidence" for the slope in this problem (assume the interval we constructed from data is $(c,d)$)?