Since January 1966, the Bureau of Labor Statistics has reported food price indexes both on a seasonally adjusted and unadjusted basis. The seasonal factors used to adjust food price indexes show that food prices typically reach their high point of the year in July. The seasonal increase of 1.1 percent from June is the largest monthly change within the year. After July, prices usually decline seasonally into the fall months. November prices typically are 1.3 percent lower than the July high. These changes are much greater than twice the estimated standard deviation of the seasonal factors of about 0.15 percent.
