<正>'The industry will be changed forever by this recession.What will it look like on the other side?'According to a new report from audit and consulting firm PricewaterhouseCoopers,advertising expenditures worldwide will total $467.3 billion by 2013.In case that seems to suggest the ad industry will have bounced back in four years' time,consider this:The figure is,in fact,about 2.5 percent lower than 2008's tally of $479.3 billion. A growing number of advertising and marketing officials now believe a fundamentally new advertising and marketing sector will emerge from the recession—one that's slow to recover its previous spending levels and forced to be leaner and meaner.