Refining the empirical Phillips curve with time varying parameters indeed explains missing disinflation during GFC. For instance, Constâncio (2015) illustrates for the euro area that, once the parameters are allowed to change over time, the
Phillips curve remains an important vehicle at the ECB to discuss inflation dynamics. Using these timevarying parameters instead of constant parameters not only accounts for the missing disinflation during the GFC but also improves the fit of the Phillips curve during the prolonged period of low inflation after 2012 in the euro area.