How can I get a total count of students projected below 40%?

video1.0<iframe src="https://www.loom.com/embed/9a4299c556994c3b938b779a611406f8" frameborder="0" width="1906" height="1429" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>14291906Loomhttps://www.loom.com14291906https://cdn.loom.com/sessions/thumbnails/9a4299c556994c3b938b779a611406f8-c9d0295214b66f74.gif99.542How can I get a total count of students projected below 40%?