A Number group is a set of numbers that results from dividing all the numbers in the
number field into groups of numbers
to be studied. Often the numbers are divided into groups of ten, but if your number
field is very low or groups of ten would leave a small set of numbers out (like in a 53
number field), then smaller
number groups can be chosen to even out the groups. More often than not, one or more
number group is not represented in a drawing. If you are using groups of 10, for
example, a drawing might be missing a number from the 20s. Example: 3-7-12-30-33-41.
Use the Number Groups Bias Tracker to track number groups.