Does this problem still occur? Did you try to retrieve the data for other periods (e.g. last year)?
I had the same experience, but with some guidance I found that from "My Dashboard" next to "Total Observations there is a settings icon. Click that to select your observations period to be "Total".
The same problem is happening to me now.
And, selecting the "Total" in dashboard does not seem to solved the problem on the Chart: I keep seeing "No data to show" on the chart.
Any other things I should do?
Thanks a lot.