I was working with charts and ended up with something like this. it is not that clear to see the date and value. The data points look crowded. we could obviously increase the width of the chart, provide an useful tooltip so we could get better understanding of the data.
because of any number of reasons both of the options might not be suitable. more over the chart doesnt have any interactivity. I wanted to add the functionality of user being able to select the range of dates and chart would reflect that. we could easily acheive that using some controls to filter the date ranges etc. but here is what I came up with.
You can see a demo here.
you ctrl+click and drag on the chart(Plot Area) to select the range we want to focus on and when the mousebutton is up, the chart is drawn for the range selected. To undo the zoom and go back to original display of the chart, just click on the chart(Plot Area).
you can download the code from here