A logarithmic absorption scale is employed, such that an absorption (A) of "one" indicates 90% of the light is absorbed, and an absorption of "two" indicates 99% of the light is absorbed. To achieve these figures, the following relationship is used; A=log10(Io/I), where (I/Io)(100)=%transmission. The shape of the absorption spectrum is valuable in recognizing the areas of highest and lowest absorption, and different shapes can represent the effects of different molecules. The precise value of each peak and valley in the spectra is calculated to facilitate further analysis.