First, you could contact the league secretary. If this was a USBC certified league, the USBC's website at bowl.com has an average lookup feature.
Book averages are typically calculated by using the ending average of a certified league, providing the average has at least 12 games (or 21 depending on the situation). If a player has bowled multiple certified leagues in a season, each league will have it's own book average, however the highest of the averages is what the bowler will be using normally for tournaments for the following year.
Delaware averages more inches of rainfall per year
There is a "yearbook" put out each year. This will contain the averages of all the sanctioned bowlers in your locale. If you do not have access to one, ask your league secretary or the front desk clerk for one. They should have one.
Based on data from the past 30 years, Mississippi averages about 40 tornadoes per year.
Bowling for Soup formed in Wichita Falls, Texas in 1994
It averages every year doesn't it?
Baytown averages 48 inches a year.
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A KFC Restaurant General Manager averages about $42,900 per year, while an Assistant Manager averages about $30,297 per year.
Portland gets more rain than Seattle. The rainfall averages 37.5 inches per year in downtown Portland. Portland averages 155 days with measurable precipitation a year. Seattle, on the other hand, averages 37.1 inches of rainfall per year.
1939
Tennessee averages about 30 tornadoes per year.