WASHINGTON — The majority of restaurant operators who participated in the National Restaurant Association’s Restaurant Industry Tracking Survey said traffic remained slow during June, representing the 13th consecutive month of sales declines. Only 22% of restaurant operators reported a same-store sales gain between June 2008 and June 2009, down from 26% who reported a sales gain in May, and the lowest level in the seven-year history of the N.R.A.’s Restaurant Performance Index, which is derived from the tracking survey. Sixty-one per cent of restaurant operators said they experienced a same-store sales decline in June.

"While there are signs that suggest an improvement may be on the horizon, the latest figures indicate that the restaurant industry’s recovery has yet to gain a firm foothold," said Hudson Riehle, senior vice-president of research and information services for the N.R.A. "Restaurant operators continued to report declines in same-store sales and customer traffic in June, and their outlook for sales growth in the months ahead remains mixed."

The tracking survey’s Expectations Index, which measures restaurant operators’ six-month outlook, stood at 99 in June — down 0.7% from May and its second consecutive decline after rising to a 19-month high in April.

The decline in the E.I. was largely due to restaurant operators’ dampened outlook for sales growth in the months ahead. Twenty-four per cent of operators expect to have higher sales in six months, compared to the same period in the previous year, down from 29% last month. In comparison, 33% of restaurant operators expect their sales volume in six months to be lower than it was during the same period in the previous year, matching the proportion who reported similarly last month.

Restaurant operators are also less optimistic about the economy, compared to recent months. Twenty-six per cent said they expect economic conditions to improve in six months, down from 34% who reported similarly last month. Meanwhile, 26% of operators expect economic conditions to worsen in six months, up from 17% who reported similarly last month.

The overall R.P.I. for June stood at 97.8, down 0.5% from May and its 20th consecutive month below 100, according to the N.R.A.