TOKYO (AFX-ASIA) - Japanese tertiary index data this week will provide clues to second quarter GDP growth after the sharp rise of 1.4 pct quarter-on-quarter in the January-March period, economists said. "After the 5.7 pct annualised jump in GDP in Q1, the April figure for the tertiary index will give some clue as to how well Q2 has begun," Dresdner Kleinwort Wasserstein economists said. "At the moment, the consensus view appears to look for a small decline in GDP in this quarter, which is in line with our own forecast," they said in a note. Richard Jerram, chief economist at ING, also noted interest in trade figures "for any signs as to whether the recent surge in exports is starting to slow". "However, it is much too early to expect to see any effect on trade volumes from the recent yen strength," he said. The following lists the range of forecasts given by surveyed economists for key economic indicators to be released this week (compared with previous period data or previous estimate): JAPAN MAY TRADE BALANCE, Thursday (8:50 am): -- 115.0-550.0 bln yen (76.0 bln; consensus 334.1 bln) HSBC Securities wrote: "The trade surplus is expected to rise for the third time in a row, and the trend should be improving with exports recovering." JAPAN APRIL TERTIARY INDEX, Friday (8:50 am): -- down 2.8-up 0.3 pct mth-on-mth (up 1.2; consensus down 1.0) HSBC Securities wrote: "The tertiary industry activity index is expected to have fallen on the month in reaction to last month's rise. With industrial production rising by 0.2 pct month-on-month in April, the all-industry activity index is not likely to fall as much as the tertiary sector index." tb/jr