United Airlines announced the first airfare increases of the year, a modest $4 to $10 on domestic routes. The announcement this week marked the first fare hikes of the year and, as of Friday afternoon, had been matched by Delta, with American and US Airways taking a \"minimal matching\" approach, Rich Seaney of FareCompare.com told the Chicago Tribune. The United action, coupled with Star Alliance member Air Canada, took effect Thursday and affected 1 million fares. Seaney told the Tribune that only seven of 15 attempted air fare increases last year were successful.