The state is forecasting Hawaii’s economy to improve modestly this year, helped by double-digit growth in visitor spending.

The latest forecast calls for state gross domestic product to expand by 1.4 percent in 2011, after adjusting for inflation. That’s up from a forecast of 1.3 percent growth delivered three months ago by the state Department of Business, Economic Development and Tourism.

Leading the way will be a 13.1 percent increase in visitor spending to $12.6 billion. DBEDT’s forecast three months ago was for a 12 percent increase in visitor spending.

“The double digit visitor expenditure growth is very encouraging,”said DBEDT Director Richard Lim. “Too often we focus on how many visitors are arriving. It’s very important to look at how much they are spending, and this is the driver of our economy.”