US advertising revenues (excluding Political and Olympics – P&O) grew 1.6% in Q4 2011 and 3.1% for the full year to reach $171.7 billion, according to May 2011 figures from MagnaGlobal. Including P&O into the equation, the company reports a more moderate 1.7% year-over-year growth. This compares to recent Kantar Media figures, which reported a 1% decline in Q4 spend, with advertising expenditures for the year inching up 0.8%. Looking ahead, Magna Global expects core media advertising revenues to grow 2.2% this year, rising to 4% when factoring in P&O. Read the rest at Marketing Charts.