Two positive coefficients are associated with past languages: ASP/ASP.NET (+$2,403) and Scala (+$13,920). Interpretation is not straightforward; it can be spun negatively, since the respondents got a big boost in their expected salary when they stopped using them, but it could also be a understood in a positive light: these languages served as important career steps or learning paths. Respondents who used Scala in the past were more likely to be computer science majors (64% vs. 52% of the whole sample) and were more likely to work on collaborative code, read/edit code of others, plan software projects, work on projects that require real-time data analysis (27% vs. 17%), and do backend web development; it is possible that the past-Scala-use coefficient indicates knowledge of some of the above features (and perhaps hidden features, such as level), which in turn affect salary.