For anyone actually hoping to apply this, a simplified version of the Philips Curve can be approximated using the following function:

f(x) = % change in unemployment rate

f(x) = (-1/2)((Change in GDP)/(GDP)-4)

This assumes that unemployment will be relatively steady when GDP growth is about 4%. A perfect example of this is Canada in 2001. GDP grew by 4.0% annually and unemployment grew to 7.6% from 7.4%.

Obviously, this is just a rule of thumb. Interestingly, though, a great many political and diplomatic decisions are made on the basis of simple ‘back of the napkin’ calculations like this.