The source data now has 2 digits precision, instead of 4

[vitorbaptista]

It's not really an issue, but I was re-running the code and I found it curious. For example, compare the GCAB yearly data on http://www.ncdc.noaa.gov/cag/time-series/global/globe/land_ocean/ytd/12/1880-2017.csv with what we have in our repository, https://github.com/datasets/global-temp/blob/cecb0653d86aefc3ee66b4a23796bbf88865effc/data/annual.csv.

Any idea on why they done it?