Depends on how you define 'end run time'.
A typical report studio report would involve a whole series of actions like compiling the right SQL on the server, sending requests to the database, fetching the data to the server, performing server-based actions (like aggregate filters) and finally generating the output into either html,pdf etc. The run-time might depend heavily on execution of the queries, but it may also involve a heavy load on the server.
Ties Blom