Size Requirement of SQL Database

I have been asked this question in an interview that how much would be the DB size for a standalone SQL server if 650MB of data is processed every month. I couldn't give any answer to this question in my interview and later on didn't find any answer either. Any help would be highly appreciated.

This is an open-ended interview question that doesn't have a precise answer. The interviewer might expect you to ask additional questions for clarity.

Actual space requirements will depend on what is meant by "processed" (inserted?), data retention (are data ever deleted?), column data types, indexes, storage overhead, use of compression features (including columnstore), plus additional free space for routine maintenance.

StackExchange Database Administrators Q#285952, answer score: 13