[R-sig-Epi] Probability of falling incidence

[Ralf Finne]

Hi everybody.

Below are the incidence numbers for  end-stage renal disease in the
Helsinki region for the past five years.

The following question has arisen:

What is the probability  that the decreased  incidence for 2006
is due to random variablilty and not caused by any systematic effect?

2002   75
2003   73
2004   69
2005   65
2006   28

Are there any solutions available in R?

Very thankful for your answers

Ralf Finne
Svenska yrkeshöskolan 
Vasa Finland