In Q4 2003 online ad spending was $2.2 bln, a 38% increase YTYL. The number of online advertisements sponsored by the automotive industry increased 75% in 2003, according to Nielsen/NetRatings, while online advertisements by the telecommunications companies increased 31%. Over all, the number of online advertisements delivered in 2003 increased 4%, reaching 1.09 trillion impressions. An impression is a single appearance of an ad on a user's computer screen. Although 4% was not overwhelming growth, the fact that spending increased 20% indicated a healthy market.