By Jessica Frank-Keyes The government must fix the “antiquated” business rates system which is dampening productivity and growth, firms and the Confederation of British Industry (CBI) has urged. A cross-sector panel including retail and manufacturing firms met to develop proposals to improve the current system in a bid to boost investment and supercharge the economy. CBI chief executive Rain Newton Smith said: “It’s time to fix the antiquated business tax system once and for all, seizing the chance to boost investment and grow the economy. “The current system is simply not fit for purpose, and…