c. After you file 100 to 200 records in such a system, a pattern formed by color and
blocking of the folders emerges. In a properly instituted and maintained terminal digit,
color coded, and blocked filing system, it is impossible to misfile a record in an area
greater than 1/100 of the total file area without the misfiles being visible. A folder misfiled
with respect to the left digit of its primary number (for example, a "92" that has been
inserted among the "82s" attracts attention because it is a different color. If, within a color
group, the diagonal pattern form by the blocking is interrupted, it is because the folder
whose blocking causes the break was misfiled with respect to the right digit of its primary
number. For example, a "92" inserted among the "95s" shows a break in the diagonal
pattern as shown in figure 1-17.
Figure 1-17. Diagonal pattern of filing of DA Form 3444-Series.