Hi Troy, There's some differences in definition of BETA out there. Value Line's BETA is fairly long term, so doesn't change often or much when it does change. Here's their definition:
"Beta—a relative measure of the historical sensitivity of the stock's price to overall fluctuations in the New York Stock Exchange Composite Index. A Beta of 1.50 indicates a stock tends to rise (or fall) 50% more than the New York Stock Exchange Composite Index. The ''Beta coefficient'' is derived from a regression analysis of the relationship between weekly percentage changes in the price of a stock and weekly percentage changes in the NYSE Index over a period of five years. In the case of shorter price histories, a smaller time period is used, but two years is the minimum. The Betas are adjusted for their long-term tendency to converge toward 1.00."
Unfortunately they don't discuss BETA of less than 1.0, but it's been through osmosis that I've decided that a 0.80 in Value Line's mock up means that it moves opposite the market's move. A 0.45 would move opposite the market at an accelerated pace.
Other data suppliers will differ on how BETA is calculated. Value Line never shows a "negative" BETA, for instance and some services do.
Best regards, Tom
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