\Header{co2}{Mauna Loa Atmospheric CO2 Concentration}
\keyword{datasets}{co2}
\begin{Usage}
\begin{verbatim}data(co2)\end{verbatim}
\end{Usage}
\begin{Format}
A time series of 468 observations; monthly from 1959 to 1997.\end{Format}
\begin{Description}
Atmospheric concentrations of CO2 are expressed in parts per million
(ppm) and reported in the preliminary 1997 SIO manometric mole
fraction scale.

The values for February, March and April of 1964 were missing and
have been obtained by interpolating linearly between the values
for January and May of 1964.\end{Description}
\begin{Source}
Keeling, C. D.  and T. P. Whorf,
Scripps Institution of Oceanography (SIO),
University of California,
La Jolla, California USA 92093-0220.

\url{ftp://cdiac.esd.ornl.gov/pub/maunaloa-co2/maunaloa.co2}.\end{Source}
\begin{References}
Cleveland, W. S. (1993).
\emph{Visualizing Data}.
New Jersey: Summit Press.\end{References}

