tweak description (by Eric Lindblad)

git-svn-id: https://svn.r-project.org/R/trunk@88389 00db46b3-68df-0310-9c12-caf00c1e9a41

Author: smeyer

src/library/datasets/man/uspop.Rd

@@ -8,8 +8,8 @@
 \alias{uspop}
 \title{Populations Recorded by the US Census}
 \description{
-  This data set gives the population of the United States (in millions)
-  as recorded by the decennial census for the period 1790--1970.
+  The population of the United States (in millions)
+  at the 19 decennial censuses from 1790 to 1970.
 }
 \usage{uspop}
 \format{A time series of 19 values.}
@@ -18,7 +18,6 @@
   \emph{Interactive Data Analysis}.
   New York: Wiley.
 }
-% FIXME: missing \references{}
 \examples{
 require(graphics)
 plot(uspop, log = "y", main = "uspop data", xlab = "Year",