The best source of information for year-to-year visitor statistics is the Las Vegas Convention and Visitors Authority, whose Las Vegas Visitor Profile studies have proven to be solid. These reports are produced annually and the 2009 numbers likely won't be available until late spring or early summer 2010.
However, the 2007 and 2008 figures are available and the latter seem to indicate the downward trend that we all instinctively know is highly likely. Here are some of the numbers:
While there are no figures available for 2009 as yet, anecdotal evidence certainly supports the theory that gambling budgets are being cut as a result of the current economic climate. Las Vegas' gambling win has been down for 17 consecutive months and win is directly correlated to handle (how much is wagered), which is directly correlated to gambling budgets. Hence, we'll bet dollars to donuts that the next official study will show a significant decline in gambling budget for the average visitor.
One final aside: We know our visitors are far from "average," as was borne out by the last LVA reader poll we conducted on the subject of gambling budgets. 27% of respondents -- the winner -- claimed to gamble $1,000-$2,000 per trip -- approximately double the average -- while 14% gamble $2,000-$5,000.