When using graphgooglechartapi to create graphs of your data, the first Month (in "monthly history") with more than 3 characters in the HTML source code ( März in German) will only be displayed as "M" and the rest is missing, togehter with the remaining month.
See attached screenshots of the same data, one with a German browser, one with english settings. This is related to the HTML source code conaining the German "Umlaut" to display "ä":
(extract of source code for according graph frame)
I was playing arround with according variables "labellength" in graphgooglechartapi.pm but that did not work out.
But I have to confess, I am not good with perl.