CO2g per KWh is the standard metric for "how much a countries electricity pollutes".
Tldr China's is 580 and improving. USA is 370 and improving at a similar rate (this obviously might change under the current administration).
Others worth pointing too is Sweden (40gCO2) which is a good marker of what's possible for a wealthy country and India (700gCO2) because as a country with a lot of economic development and recent historic poverty, it shows why China's improvement is worth noting.
EDIT: I probabably implied that China and USA should be compared in terms of their improvements, but didn't mean too! I figure Lemmy is a mostly USA centric place, so thought that was a good benchmark. Comparing USA to similar wealthy, established enconomies like European countries, it's improving a lot slower. Comparing China to fast developing countries like India or Nigeria (probably a messy comparison) shows its improving faster than you'd expect.
What a weird graph, doesn't tell us anything, why not an energy mix graph to show coal increasing in the energy mix? Oh it isn't? These coal factory's are made to shut older ones? Ohhh you're not very smart