4.3) Exponential Growth

The positive feedback loops described in section 2.1.2 result in exponential growth:

Examples of systems that exhibit this behaviour are:

• A savings account with an interest rate:
  the increase in the savings depends on the previous total quantity in the account
• A mine which is being depleted:
  the output decreases depending on how much is left in the mine
• A human or animal population with a given birth rate:
  the increase in population through births depends on the past size of the population

In the following, we will see some examples of what appears to be exponential growth.