Qdate to year

[Jamir Abutaleb]

Hi all, I have a variable "qdate" that only contains the last quarter of a year. I want to convert that to "year". So from the first example to the second.

* Example generated by -dataex-. To install: ssc install dataex
clear
input int qdate
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end
format %tq qdate

* Example generated by -dataex-. To install: ssc install dataex
clear
input double fyear
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end

[Nick Cox]

Here are two ways to get the year. Both follow from reading

help datetime

which is essential if you have dates in Stata.

gen year1 = year(dofq(qdate))
gen year2 = 1960 + floor(qdate/4)

The first method is to push quarterly dates into daily dates and take the year out using nested functions. The second method is based directly on definition of quarterly dates as counted from origin 1960Q1 = 0. It follows that 0 to 3 mean 1960, 4 to 7 mean 1961, etc.