The Following Table Gives the US Domestic Oil Production Rates

The following table gives the US domestic oil production rates (excluding Alaska) from 1987 to 2002. A regression equation was fit to the data and the residual plot is shown below.
$\begin{array} { c | c c c c } \text { Year } & \text { Millions of Barrels per Day } & & \text { Year } & \text { Millions of Barrels per Day } \\\hline 1987 & 6.39 & & 1995 & 5.08 \\1988 & 6.12 & & 1996 & 5.07 \\1989 & 5.74 & & 1997 & 5.16 \\1990 & 5.58 & & 1998 & 5.08 \\1991 & 5.62 & & 1999 & 4.83 \\1992 & 5.46 & 2000 & 4.85 \\1993 & 5.26 & 2001 & 4.84 \\1994 & 5.10 & 2002 & 4.83\end{array}$

Does the residual plot suggest that the regression equation is a bad model? why or why not?