I'm a Houdini Newbie, and I'm following a tutorial on Pop Grains which is very good.

Tutorial is here :
https://vimeo.com/132847114 [vimeo.com]
TimeCode : 37:20

Towards the end he adds a proximity point and calculates 1000 grains to fall every frame based on the distance to the point. The expression used on the force node is :

force*=@id <(@Frame *1000);

I've been trying to get 50 grains to fall per frame until it reaches frame 50. At 50 frames and above I would like 1000 grains to start to fall per frame.

Is this possible with expressions ?

Thanks