On March 11, there were 11 reported cases in the U.S.
On March 24, there were 37 reported cases in the U.S.
On April 2, 72 cases.
The current trend suggests the number of cases in the U.S. are roughly doubling each week.
On a hypothetical basis, if the number of cases doubled every week, in 23 weeks everyone in the U.S. would have SARS.
I definately do not expect this trend to hold up, but I will be glad to see it break.