Economists focus on this restricted figure because they consider energy and food prices volatile - subject to sharp fluctuations that can distort the overall ndex.

The production of major food staples such as corn is subject to sharp weather-related fluctuations.

Last year, when the sharp fluctuations began, they raised concern about whether individual investors would be caught up and crushed in the market's sudden swings.

In contrast, given the sharp fluctuations of the yen against the dollar over the last year, the currency risks are much greater.

The climate of Pyatigorsk is moderately continental, without sharp fluctuations of annual and daily temperatures.

Moreover, highly volatile world markets for both commodities caused sharp fluctuations in government revenues and made development planning difficult.

With the price of crude oil in sharp fluctuation, almost all the big carriers have hedged their fuel costs, though to varying degrees.

These factors include solar or gravitational anomalies, sharp fluctuations in atmospheric pressure and magnetic disturbances.

But layered on top of this trend are sharp fluctuations in the fortunes of regions tied to major industries.

Populations slowly settled into their sizes, but there were frequent sharp fluctuations.