What is the S button on Volvo s40?

It switches the control of the drivetrain (engine + transmission) into and out of the Sport mode. In this mode, the power from the engine is available quicker than in the non-Sport mode. The drivetrain computers will maintain higher RPMs, and do aggressive shifting. Of course the fuel economy is worse that way.

What year is the s40 Volvo and where exactly is the "S button" located ?