What is Variance? This measures the difference between the stock price over different times and the average price. Technically, variance is a statistical term representing the average of the squared mean difference. Because variance is additive through time, we can annualize a daily variance by multiplying by the number of business days in a year, 252. Related articles What are VIX Futures? What is Long Skew? What is VIX Ref? What is Volatility Skew? High Impact Scanner