Here's the approximate percent composition of gases in Earth's atmosphere:

* Nitrogen (N2): 78.08%

* Oxygen (O2): 20.95%

* Argon (Ar): 0.93%

* Carbon Dioxide (CO2): 0.04%

* Other Gases: ~0.001%

Other Gases include:

* Neon (Ne)

* Helium (He)

* Methane (CH4)

* Krypton (Kr)

* Hydrogen (H2)

* Ozone (O3)

* Xenon (Xe)

Important Notes:

* Water Vapor (H2O): The percentage of water vapor in the atmosphere varies greatly depending on location and weather conditions. It can range from near zero to about 4%.

* Trace Gases: The "Other Gases" category contains many gases in very small amounts. These can be important for various atmospheric processes.

* Constantly Changing: The composition of the atmosphere is not static. It's influenced by natural processes, human activities (like pollution), and climate change.

Let me know if you'd like more details about any specific gas!