Tribune Co., the parent company of the Los Angeles Times and KTLA-TV (Channel 5), reported a 1.7 percent drop in revenues between July 2004 and July 2005, as most categories of advertising at the Times posted steep declines.

The Chicago-based media company did not break out revenues for individual properties, but the company reported that advertising volume in the full run of the Los Angeles Times decreased 11.1 percent between July 2004 and July 2005, the sharpest decline among Tribune papers. Advertising volume in partial runs of the Times was down 8.0 percent, which also was the weakest performance among the company’s newspapers.

The Times’ advertising woes were exacerbated by the loss of ads from General Motors Corp., which pulled out of the paper earlier this year over complaints about editorial coverage. GM recently restored its advertising in the Times.

Tribune, which owns 11 newspapers including the Chicago Tribune, 26 television stations and the Chicago Cubs, said its 1.7-percent overall decline left it with $523 million in total revenues in July.

Revenues for Tribune’s publishing division, of which the Los Angeles Times is the largest component, were $360 million, down 0.7 percent from the same period in 2004. Broadcasting and entertainment group revenues in July were down 3.9 percent to $154 million.