Here is the methane concentration graph the from the Soywa flask. Missing data is indicated by -999.99.

![Soywa 1986-2013](https://dl.dropboxusercontent.com/u/61621163/Images/syoccgg.png)

src: ftp://aftp.cmdl.noaa.gov/data/trace_gases/ch4/flask/surface/ch4_syo_surface-flask_1_ccgg_event.txt