Japan's economy grew 1.6% in the first quarter of 2013 before a sales tax rise, posting the strongest expansion in more than two years, revised data showed today. 

The expansion was slightly faster than the initial estimate of 1.5% growth. 

Today's revised data confirmed the economy had staged the biggest expansion since a 2.6% growth in the three months from July to September in 2011, when it was rebounding from the earthquake-tsunami disaster in March of that year.

The nation's cash registers rang up big sales in the January-March period ahead of the April 1 consumption tax rise from 5% to 8%. 

Millions of shoppers scooped up everything from cars and refrigerators to televisions and alcohol in a buying spree. But the rush of demand has dented activity in the following months.