year combination price

2015 1 0.5

2016 1 1

2015 2 2

2016 2 2.5

2015 3 1

2016 3 1.5







Hey guys, i need help creating a new variable in which i need to find the difference in price from 2015 to 2016 for each combination. for example, the first row of the new variable would be (0.5-1) . second would be (2-2.5) and so on..




would really appreciate some help on this