The company issued a trading update in which it predicted a drop in turnover for the nine-month period to 23 October 2009 of 14%, while operating profit will fall year-on-year by 37% for the period.
It believes that full year operating profit should come in at between €170m (£152m) and €190m.
Group advertising revenue was down 19% year-on-year, compared with 19.6% in the first half.
But, INM said in the statement that its performance since the half-year report had "marginally improved".
The 37% drop in the second half of the year is compared with a 45% year-on-year decline in the first half of the year, which INM attributed to "stabilisation in advertising revenue and continued strong cost management across all regions".
It said: "Based on still limited visibility, the advertising trends experienced in September and October remain challenging and are expected to continue for the remainder of 2009."
