Within five years, the income needed to maintain a middle-class standard of living for a two-parent family with two school-age children in Massachusetts jumped nearly 50 percent, according to the MassINC Policy Center. This increase, from $117,000 in 2020 to $174,000 in 2024, is a much faster rise than in the past and exceeds the rate nationwide. It also outpaced the inflation rate by 28 percentage points, analysis by the Massachusetts research nonprofit shows.