collapse (sum)
  vship valimpall valimpLDC valexpall valexpLDC
  realvship realimpall realimpLDC realexpall realexpLDC
  realvshipDRso2  realvshipDRno2  realvshipDRco   realvshipDRvoc
  , by(year);
outsheet year
  vship valimpall valimpLDC valexpall valexpLDC
  realvship realimpall realimpLDC realexpall realexpLDC
  realvshipDRso2  realvshipDRno2  realvshipDRco   realvshipDRvoc  
  using  "C:\Arik\Projects\AfterNAFTA\AER figures and tables\Part1data_2", replace;


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