Y Axis and Navigator Series REQUIRE Numbers not Strings

[Eric @ NASS]

Hello! I am working with Highstocks for the first time, but before getting into the details of my problem, let me say...
My data is in a large csv. For coding simplicity, I am sourcing it cross-domain, which IE8 will allow if user approves. Ultimately, the csv would be hosted with the HighStocks code and Firefox (etc.) would be compatible.

I began by making cosmetic changes to the Demo Gallery's single line series example, while still using the AAPL Stock Price data. My working changes...
http://jsfiddle.net/Dgmbf/

Then to change the data to my desired source, a csv with wheat data from quickstats.nass.usda.gov, I just changed the series option "data : data" to "data : yield". The values appear correctly in the tooltips, but the y axis and the navigator series vanish...
http://jsfiddle.net/Dgmbf/1/

I want both automatic scaling of the y axis and a visible navigator series. I've compared the JavaScript objects "data" and "yield" by issueing them in alerts and by writing them to the document. Obviously, their values differ, but their construction looks the same to me. What am I missing?

Thank you!

I was missing that "yield" contained stringValues instead of numberValues. Which was a simple fix by (+stringValue). The example is updated...
http://jsfiddle.net/Dgmbf/3/

All is now well!