Time Series Data

Hi All,

I'm trying to analyze some time series data and I have run into  
difficulty. I have decadal sun spot data and I want to separate the  
very regular periodic function from the trend and noise. I looked  
into using stl(), but the frequency of the time series data must be  
greater than 1 for stl(). My data covers a 1000 year interval from  
9095 BP to 8095BP and the frequency is, therefore, 0.1 (because the  
data are decadal). I've tried changing the frequency, but the only  
frequency that creates a plot of the time series data which matches  
the raw data is 0.1. Is there anything I can do to the data that  
will make it more amenable to stl(), or is there another package  
that I could use for decomposing the signal that does not require  
that the frequency of the time series to be greater than 1? Thanks,