falling tendency

These changes have led to significant increases in labour productivity on the railways, despite the falling tendency of rail traffic.

In short, you are constantly tending to fall in one direction or another, and the muscles of your trunk and legs must constantly adjust their tensions in order to counteract and neutralize these falling tendencies.

Shane Mage, The Law of the Falling Tendency of the Rate of Profit; Its Place in the Marxian Theoretical System and Relevance to the US Economy.