Sweden's economy continued its rapid expansion in the third quarter, easily beating analyst expectations and registering the highest year-on-year growth rate on record, the national statistics agency reported Monday.

The Scandinavian country's economy swelled by a much better-than-expected 2.1 percent compared to the previous three-month period, and year-on-year, the growth was even steeper, at 6.9 percent, Statistics Sweden said.

"The high GDP figures are of course due to the deep drop we experienced last year," Peter Buven, an analyst with the statistics agency, told the TT news agency, pointing out that Swedish GDP shrank 5.4 percent in the third quarter of 2009.

Nonetheless, Buven pointed out that the figures announced Monday were the highest since Statistics Sweden began its quarterly measurements in 1970.

"The previous highest growth levels were measured in the second quarter of 1974 and in the second quarter of 2000. Both times, GDP grew 5.8 percent," he said.

Before 1970, the statistics agency only registered yearly growth numbers, but the third-quarter hike this year "is most probably the highest since 1950," Buven said.

The Swedish growth figures, which already soundly beat analyst expectations in the second quarter, were again far better than expected in the July-to-September period.

According to a poll by the Dow Jones Newswires, analysts had anticipated a 1.3-percent hike compared to the second quarter and an increase of 5.6 percent compared to the third quarter of 2009.

Statistics Sweden meanwhile slightly revised down the growth numbers for the the April-to-June period, showing that Sweden's GDP grew 4.5 percent year-on-year. Quarter-on-quarter, the number remained at 1.9 percent.

Contributing to the strong third-quarter growth, according to the statistics agency, was a 3.5-percent increase in household consumption expenditures and a 1.8-percent jump in government consumption expenditures.

Changes in inventories meanwhile alone contributed to 2.9-percent of the GDP increase, Statistics Sweden said.

Sweden, which emerged from recession in the second quarter of 2009 and saw growth quickly picked up in the first quarter of 2010, now has one of Europe's strongest growth rates.