Fig. 14. Modified Snellen formula (1/V = M × D) for near vision. Columns indicate reading distances. Rows indicate letter sizes. The resulting reading acuity values are found at the intersections. The large number in each box represents the M × D value (magnification requirement). The small number represents the visual acuity value. The visual acuity values are arranged in diagonal bands. The same visual acuity value can be represented by many different combinations of viewing distance and letter size. For each diagonal band, the outer edge of the figure indicates the ranges of vision loss in ICD-9-CM. The J designations in the first column refer to values found on current charts. These are different from Jaeger's original sizes, which are shown in Figure 7.