  We demonstrate the effectiveness of the logistic function to model the
evolution of two economic systems. The first is the GDP and trade growth of the
USA, and the second is the revenue and human resource growth of IBM. Our
modelling is based on the World Bank data in the case of the USA, and on the
company data in the case of IBM. The coupled dynamics of the two relevant
variables in both systems - GDP and trade for the USA, and revenue and human
resource for IBM - follows a power-law behaviour.
