The Perfect Exponential Curve fitting in MS Excel

Curve fitting is the process of constructing a curve or mathematical function, that has the best fit to a series of data points. Fitted curves can be used as an aid for data visualization, to conclude values of a function where no data are available, and to summarize the relationships among two or more variables.
Equation for Exponential Decay Curve is, $$Y=\frac{1}{B}.e^{\left(\frac{A-x}{B}\right)}$$Where $A$ is Position,
$B$ is Scale parameter