I am trying to create a variable based on employment data taken from a survey done over several years. Currently, I'm working with data that takes on a value of 0 if a person is unemployed and if they are employed, the data point represents what year of the survey the person is in and what number job they are in that year. To illustrate, if a person is in the 3rd year of the survey and is on their 2nd job that year, that would be represented as a value of 302 in the dataset. I'd like to create the variable such that it indicates what number job the person is in over the entire length of the survey. Ideally, it'd look like this:

Person employment job number
1 0 0
1 101 1
1 101 1
1 102 2
1 102 2
1 0 0
1 103 3
1 201 4
1 201 4
1 202 5
1 203 6

and so on.

I've tried using several forms of cumulative addition but can't seem to figure out how to manipulate the numbers that are bigger than 200 or get them to take on the values I want. Any advice is appreciated!