Creating one variable

[Paris Rira]

Hi all,

I am going to create a variable in a way that variable in -SIMMIdt in year 2015 - SIMMIdt in year 2010 in the same region.
for example: .01467756 -.01926798=

clear
input int year byte region float SIMMIdt
2010 1   .01926798
2015 1   .01467756
2010 2  .018267224
2015 2  .014039835
2010 3   .02406379
2015 3  .022580145
2010 4  .010038483
2015 4 .0091869775
2010 5   .00555628
2015 5   .00540444
2015 6  .008160894
2010 6  .010712284
2015 7  .012789745
2010 7  .015284938
end

Any ideas appreciated.

Cheers,
Paris

[Clyde Schechter]

On the assumption that all observations have either year == 2015 or 2010, no other values:

assert inlist(year, 2010, 2015)
by region (year), sort: gen wanted = SIMMIdt[2] - SIMMIdt[1]

[Paris Rira]

Thank you so much Prof Clyde,

It worked perfectly.
To drop duplicates I used :

input int year byte region float(SIMMIdt wanted)
2010 1   .01926798   -.004590418
2015 1   .01467756   -.004590418
2010 2  .018267224  -.0042273887
2015 2  .014039835  -.0042273887
2010 3   .02406379   -.001483647
2015 3  .022580145   -.001483647
2010 4  .010038483  -.0008515054
2015 4 .0091869775  -.0008515054
2015 5   .00540444 -.00015184004
2010 5   .00555628 -.00015184004
2010 6  .010712284    -.00255139
2015 6  .008160894    -.00255139
2015 7  .012789745   -.002495193
2010 7  .015284938   -.002495193
end



bysort wanted: keep if _n==_N