need help designing filter buttons on a line graph

I have a line graph that I am designing in my software. The line graph can have hundreds of data points over the years. We want to provide buttons to only look at data for lets say – 1 month, 6 months, 1 year and 5 years. Lets say the design of the graph limits showing 15 data points at max at a time. When showing data for 1 Month, we don't encounter into a problem because there are only 6 data points available. But now user selects 5 years button, how should the graph decide which 15 data points to show when there are lets say 128 data points available in the last 5 years? Any suggestions are highly appreciated!

I checked excel and noticed that excel doesn't provide any filter capability and always shows all data points