When orbiting in a specific altitude like 60,000km to 100,000km...your orbit will decrease faster beacause of the planet's atmosphere...also when orbiting 200,000km to 400,000km...it will also decrease in speed and altitude but more slower depending on how much air density,altitude(the higher the slower)......
Also...the rate of decrease in orbit,speed
also depend on the Size of the satellite,mass,surface area and etc.
Just like the international space station...
Their orbit becomes getting lower and lower over time...so you need to re-boost your station...satellites etc.
Edit no.1
Option to turn it off and on
@Iamamatrian yeah, now If it does get implemented I won't have to worry about 6 months of station falling into the middle of the ocean