BeginPackage["Wikicode`Thallium`"]
Production::usage="Production[date] gives the annual world thallium production from the specified date."
Begin["`Private`"]
Production[from_Integer]:=Select[thalliumData["Production"],DateDifference[{from},#[[1]]] >= 0&]
thalliumData["Production"] =
MapAt[{Round@#} &, #, 1] & /@
Import["http://minerals.usgs.gov/ds/2005/140/ds140-thall.xlsx"][[1,
44 ;; 74, {1, 7}]]
End[]
EndPackage[]
