High numbers are the top half of the number field of a lotto game.
For example, if a lottery's number field is 5/50, the high numbers are
25-50. Usually, it is good to play a relatively even mix of high and
low numbers.
It is much less common for a drawing to have all high or all low numbers than it is for a mix of high and low.
High lotto numbers can be tracked using the Advantage Gold lotto chart,
Low High Bias Tracker Chart.
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Screenshot of Advantage Gold, Low High Bias Tracker Chart