There is a significant relationship between project activity and developer interest on Open Source (OS) projects. Total project activity submission count number can be an indicator for gauging developer interest. The higher the project activity submission of a project is, the larger developer interest in a project. My paper proposed that applying a Submission Multiple Tier (SMT) matrix can detect the impact of developer interest on project activity. Results showed more volume of OS projects with low project activity than high. Activity submission results also showed that developers are more likely to review than correct projects, with the first priority to find and fix bugs. Further research is needed to determine the impact of project activity type on developer motivation to contribute, participate and support OS projects.