More than half a dozen affordable housing projects in California are costing more than $1 million per apartment to build, a record-breaking sum that makes it harder to house the growing numbers of low-income Californians who need help paying rent, a review of state data has found.

The exorbitant price tags mean that taxpayers are subsidizing fewer apartments than they otherwise could while waiting lists of renters needing affordable housing continue to grow.

A key driver of the increases is labor and material prices, which have soared because of inflation, supply-chain problems and worker shortages during the COVID-19 pandemic. But numerous factors within the control of state and local governments also to blame for the high cost of building affordable housing in California.