For exponential functions, they are defined by the general formula:
From the graph given in the question, we can deduce that
when
With this, we can derive the values of a and b
so that
Similarly, we can get b by substituting the value of a=200 and y=180 when x=1 into the equation
Thus the formula is
The 0.9 means that there is a loss of 10% every year
Therefore
The correct answer is
$200 at a 10% loss per year