Ad Spending Still on Shaky Ground: Spending by the nation’s 100 Leading National Advertisers seemed to finally turn the corner in 1992, rising 5.6% compared to the year before to $36.2 billion, Advertising Age magazine reported. But despite the improvement for 1992, early signs for 1993 are not good. Ad spending for the first quarter of 1993 slipped 3.8% compared to the same period last year, according to the report. The annual survey also reported that Procter & Gamble spent $2.17 billion on its 1992 advertising, a paltry 0.7% increase compared to 1991, to barely cling to its lead as the nation’s single largest advertiser. Despite the overall increase in ad spending among advertisers in 1992, the total amount spent by the Top 100 is only back to its 1990 levels, the report said.