'Generates log of US real disposable income and a white noise process WN.
'nrnd=normal random  variable with 0 mean and SD of 0.36


smpl 1959:1 1998:1
genr lyus=log(uspdispid)
genr WN= 8.03+0.36*nrnd        '8.03, 0.36=sample mean and SD of lyus.
plot WN lyus

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