The width table in the PFM file is an array of 16-bit values containing the width of each character in the font. The number of elements in the array is computed as dfLastChar – dfFirst + 2. Since the last entry is extra, it is set to zero. The width
table is optional. For example, fixed-pitch fonts do not require the table since all characters have the same width. If the table is provided, it must be placed between the PFMHEADER and PFMEXTENSION structures.