A former adviser to President George W. Bush, Malmgren is zeroing in on what’s come to be known as “shrinkflation” — where companies charge consumers the same, or more, for less. It also explains why people are so agitated by a higher cost of living, writes Malmgren, who founded London-based DRPM Group, a consulting firm. Take the Dairy Milk bar produced by Mondelez International Inc.’s Cadbury unit.