Symbol 3320 from ISO 7000 - Title/Meaning: Progress toward completion, 50% complete Function/description: To indicate that the process is 50% complete.
pay attention to orientation of symbolAdditional information: 
The lines in the first and second quadrants may be replaced with appropriate fill-in colours or progressively darker grey scale.
Own work using: iso.org/obp/graphics/grs/da72c9b9-82c3-45e2-b388-6b498d4599f1 200.png
Vectorization:  Mrmw