While imperial revenues fell, imperial expenses rose sharply. More soldiers, greater proportions of cavalry, and the ruinous expense of walling in cities all added to the toll. Goods and services previously paid for by the government were now demanded in addition to monetary taxes. The empire suffered from a crippling labour shortage. The steady exodus of both rich and poor from the cities and now-unprofitable professions forced Diocletian to use compulsion; conscription was made universal, most trades were made hereditary, and workers could not legally leave their jobs or travel elsewhere to seek better-paying ones. This included the unwanted middle-class civil service positions and under Constantine, the military. Constantine also tried to provide social programs for the poor to reduce the labour shortage.