Creating graphs and statistics

Hi,

I have a site/blog where I store my bikerides as nodes (of type 'bikeride'). I have some custom CCK fields (decimal and integer) to store things as avg. speed, max. speed, distance etc. Now I want to create a (line) graph (or chart) of this data for instance on a per month or per year basis. Things I want to show in these graphs are: total km's per week/month/year, avg. / max. speed over time (to see if it changes etc.), a bar graph to show the amount of short / medium / long rides, etc. (this last one is a bonus).

I've tried some modules, but I did'nt get so far as actualy displaying some data. Can someone point me into the right direction. I'm a internet-programmer (although not very active on PHP).

Thanks in advance,
Wilfred