I leave my Booth and swipe my doortax card.As i reach the pavement the steptax post rises and scans me.Walking along the step counters emmbedded calculate the charges.From a nearby lamppost a tiiny voice cautions me i am using more than my agreed ration of atmosphere and i will be penalalised with an on the spot fine,which is deducted immediatly.Welcome to the future.Welcome to 2020.