Average daily car rental rates rose to $69 in 2006, according to American Express Business Travel’s 2006 Business Travel Monitor published on March 26.

The Monitor tracks airfares, hotel and car rental rates for business travelers. The car rental rates are measured using corporate negotiated rates and rack rates available to the general public, although the bulk of Amex's measurements come from its corporate rates, according to David Balfour, American Express senior practice leader for car rental.

A trickle down effect has occurred in the car rental market, forcing price increases. The cost of fleets has drastically increased from 12-20 percent, putting pricing pressure on the major car rental companies. Car rental firms have pushed their prices up approximately 4.5 percent in order to offset higher operating costs.

Average daily car rental rates:
•2000 - $61
•2001 - $63
•2002 - $64
•2003 - $65
•2004 - $65
•2005 - $66
•2006 - $69

The Monitor confirmed earlier American Express predictions that costs would increase across all transient travel segments as buyer demand remains strong amid thin inventory and increased supplier operating costs.

According to The Monitor, international airfares, international hotel rates and U.S. budget-tier hotels experienced the most dramatic increases.