Consumer prices rose sharply again in March and drove the rate of inflation to the highest level in nearly 13 years, signaling greater stress on the economy as businesses grapple with supply shortages that are raising the cost of many goods and services. The consumer price index soared 0.8% in April to match the biggest monthly increase since 2009, the government said Wednesday. Economists polled by Dow Jones and The Wall Street Journal had forecast a milder 0.2% advance. The rate of inflation over the past year jumped to 4.2% from 2.6% in the prior month — the highest level since 2008.