WASHINGTON – The National Restaurant Association’s Restaurant Performance Index ended 2009 on an upward note, moving up 0.9% to 98.7 in December. The association said it was the highest level the index had achieved in nearly two years.

“The R.P.I.’s strong gain in December was the result of broad-based improvements among several index components,” said Hudson Riehle, senior vice-president of the N.R.A.’s Research and Knowledge Group. “Although restaurant operators continued to report a net decline in same-store sales and customer traffic, both registered their strongest performances since the summer of 2008.”

Although restaurant operators reported negative same-store sales for the 19th consecutive month, the overall results improved dramatically in December, according to the N.R.A. Thirty-five per cent of restaurant operators reported a same-store sales gain between December 2008 and December 2009, well above the 24% of operators who reported higher sales in November. Forty-nine per cent of operators reported a same-store sales decline in December, down sharply from 65% who reported negative sales in November.

Restaurant operators also reported an improving customer traffic performance in December. Thirty per cent reported an increase in customer traffic between December 2008 and December 2009, up from just 21% who reported higher customer traffic in November. Forty-seven per cent of operators reported a traffic decline in December, down from 62% who reported lower traffic in November.

“Along with a solid improvement among the current situation indicators, restaurant operators are increasingly optimistic about industry growth in the months ahead,” said Ms. Riehle. “More than a third of restaurant operators expect to their sales to improve in six months, the highest level in more than two years.”