Statistic graphs don't work in SoapUI Standard?

I've defined a LoadTest and have run it with SoapUI Standard. However, when I try to view the statistics graphs (either of the 2 buttons at the top of the LoadTest window) - a new mini-window appears, but no graph information is drawn. Is this only a feature with SoapUI Pro? The documentation didn't mention it was exclusive to it.

Thanks in advance...